Spinning off of this thread comparing the Mortal Kombat and Street Fighter 2 ports. One thing I don't like about comparing Street Fighter in particular is due how Capcom treated their Sega ports more or less as afterthoughts by just carrying over SNES code and assets (people even found specific Super Nintendo disclaimer leftovers by looking inside the game with hex editors) without much care for properly optimizing and utilizing the different hardware.
While they weren't as high profile as either Midway (MK) or Capcom at the time, I think it's a safe bet that most would consider SNK the only serious quality alternative to Capcom's fighters at the time. SNK commisioned Takara to develop the SNES and Genesis ports (I don't know if they also did the PC Engine/Turbografx CD ones), and JVC Musical Industries to do the Sega CD editions that appeared. And I would generally say that they technically did a much more impressive job with carrying over the Neo Geo titles to 16-bit hardware compared to how Capcom ported down from their CPS hardware. The several hardware versions of the games are all markedly different from one another and seem to be better inherently tailored for their respective systems, which makes the differences much more interesting to compare. I'm not gonna bring up the PC Engine ports much in the OP since I have next to no hands on experience with them, so I'd rather someone more savy with that system take a look at those.
Fatal Fury 2
From left to right - SNES / Genesis
Dual video of both versions running back to back
Visually the SNES obviously looks significantly better from a color standpoint. Genesis version uses a more grainy kind of style which can look pretty rough, like you can see on that statue in the background. Genesis version has slightly larger sprites though. The background props inbetween the two planes are sometimes omitted from the Genesis version as well, like you can see with that pole on the raft there. Genesis version uses dithered shadows while the SNES one uses rapidly flickering ones to give the impression of transparency. Other than that presentation wise, the SNES version has a snazzier more animated character select screen, while the Genesis version has a cool animated intro sequence you don't see in the other version.
I did check some screens of the PC Engine version, and it looks like the sprites in that one are even slightly bigger than the Genesis sprites, so that's one area where it wins out. Or maybe the screen is just stretched and I'm too stupid to notice it. Here's a pic with the PC Engine, Genesis and SNES sprites next to eachother:
Sound-wise the Genesis version has the issue with scratchy sounding sample playback, although it's far from as pronounced as it usually tends to be, and is otherwise pretty good. SNES samples are cleaner if a bit more muted and filtered, thus less clear. The consensus I've seen in discussion tends to be that people like the music in the Genesis version better.
Near as I can tell, they both play identically, although a more discerning Fatal Fury veteran could probably correct me on that.
Fatal Fury Special
From left to right - SNES / Sega CD
Video: SNES / Video: Sega CD
This is pretty much both the Turbo and Super equivalent of FF2. Apart from making the endboss Krauser playable, it also adds Ryo from Art of Fighting and reintroduces Duck King from FF1 as playable characters. There was no Genesis cartridge version for this one, but instead JVC ported it to the Sega CD addon.
It's hard to tell at a glance, but it looks like the sprites and backgrounds in the SNES version were redrawn or otherwise edited and slightly improved from Fatal Fury 2. The Sega CD version however is a world of difference. It utilizes the higher Genesis resolution mode of 320x224, and also occupies all of the screen estate without black bars. The character sprites, backgrounds, everything is redrawn to be significantly bigger and more detailed. Not only that, but it's also a lot smarter with how it uses the still more limited color palette, so it looks a lot better than FF2 Gen on that front as well. For some reason the Sega CD version still often lacks the prop elements though.
Sound-wise is where it gets weird though. The SNES version has lower fidelity voices than FF2 and thus more filtered, and in addition to that Takara also used some of the worst implementation of SNES reverb I have ever heard on the system. Everything sounds like it's being reflected in a tin chamber or something. The Sega CD version is, considering the nature of the hardware, even weirder. The music is fine as it's redbook audio recorded directly from the Neo Geo original, and it starts off promising as you hear the clear announcer voice just like the Neo Geo version during the character select screen. Once you get ingame though thinks take a real turn for the worse. The voices/sound effects are actually significantly lower quality than Takara's FF2 Genesis cartridge port. Everything is aliased to hell, and 90% of what you're hearing are the digital aliasing artifacts instead of the actual sounds buried underneath them. I don't know what the hell JVC did here when the Sega CD has much more advanced sample playback capability than the base Genesis.
Samurai Shodown
From left to right - SNES / Genesis / Sega CD
Video: SNES / Video: Genesis / Video: Sega CD
This is where things get really interesting. You'll notice that the SNES characters are really small. Like, abnormally small even for the system. The Genesis version meanwhile uses the higher resolution, with much bigger sprites and background art. Not only are the sprites big and detailed, but they're pretty well animated too. But to compensate for this, the characters don't seem to have as many unique types of animations. Haohmaru for example doesn't have his jab/thrust medium attack. Instead it's just slashes at different speeds. Logically this would also mean losing gameplay elements, since this also affects stuff like timing and hitboxes. I don't know if the Genesis version lacks anything more gameplay/system-wise since I'm far from a SS power player, but people describe the SNES version as playing more like the Neo Geo original. There's one more important difference here as well in that both the Genesis and SCD ports omit the character Earthquake who is really, really huge and likely goes beyond the hardware sprite limit at that level of fidelity. One can only speculate, but it almost makes sense that Takara deliberately gimped the character sizes in the SNES version to make room for (both in terms of screen and rom size) Earthquake's art assets. So the SNES version gets a unique advantage there. It also has the special count down game mode which isn't found in the other versions.
The sparse traditional Japanese music sounds great on both the SNES and Genesis. But for the few more filled out western-style tracks, it comes closer to the stereotypical average quality on both systems. The SNES version also has the same issues with the sound effects as Fatal Fury Special with the low quality filtered voices and awful reverb. Seems to be a recurring thing with Takara's late-era SNES ports. The Genesis version on the other hand has surprisingly great sample quality. The playback is near crystal clear (apart from the noticeable clipping inherent in the samples, though I don't regard it as distracting at all since typically classic martial arts movie SFX is just as distorted), and the port's SFX is very, very sample heavy. Not just voices but also the impacts, sword slashes, sprinting footsteps, etc. Easily the best sounding fighter on the system.
And third we have JVC's Sega CD port, which is different from the ground up compared to Takara's cartridge version (as opposed to most Sega CD versions of games that also existed on the Genesis). Same resolution but more screen space, with even bigger sprites and even more animation frames thanks to all the CD space, and doesn't omit unique animations like the Genesis does, thus the gameplay remains more arcade accurate. It still doesn't have Earthquake like the SNES version does though. Overall, the graphics are superior to the Genesis version but there are some isolated elements that seemed to be executed better by Takara. For instance you can see the snow dunes in the screenshots are just a simple color gradient on the SCD. And in some cases the color applications stick out as garish compared to Takara's colors. The SCD version also doesn't have the background referee character like the other versions.
And then we have the exact same problem with awful aliased sound effects like in Fatal Fury Special CD. The Genesis sounds are exponentially better, which again just feels ironic considering the gap in sound hardware between the two.
That's about all I'll fit in the OP. There are several more games to compare, and perhaps even those Neo Geo games that SNK didn't develop themselves like World Heroes. I just picked the ones I found most interesting. There's also Art of Fighting which has SNES, Genesis and PC Engine. Art of Fighting 2 is a SNES exclusive port and also Japan-only (Ryuuko no Ken 2). And of course there's Fatal Fury 1.
While they weren't as high profile as either Midway (MK) or Capcom at the time, I think it's a safe bet that most would consider SNK the only serious quality alternative to Capcom's fighters at the time. SNK commisioned Takara to develop the SNES and Genesis ports (I don't know if they also did the PC Engine/Turbografx CD ones), and JVC Musical Industries to do the Sega CD editions that appeared. And I would generally say that they technically did a much more impressive job with carrying over the Neo Geo titles to 16-bit hardware compared to how Capcom ported down from their CPS hardware. The several hardware versions of the games are all markedly different from one another and seem to be better inherently tailored for their respective systems, which makes the differences much more interesting to compare. I'm not gonna bring up the PC Engine ports much in the OP since I have next to no hands on experience with them, so I'd rather someone more savy with that system take a look at those.
Fatal Fury 2
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From left to right - SNES / Genesis
Dual video of both versions running back to back
Visually the SNES obviously looks significantly better from a color standpoint. Genesis version uses a more grainy kind of style which can look pretty rough, like you can see on that statue in the background. Genesis version has slightly larger sprites though. The background props inbetween the two planes are sometimes omitted from the Genesis version as well, like you can see with that pole on the raft there. Genesis version uses dithered shadows while the SNES one uses rapidly flickering ones to give the impression of transparency. Other than that presentation wise, the SNES version has a snazzier more animated character select screen, while the Genesis version has a cool animated intro sequence you don't see in the other version.
I did check some screens of the PC Engine version, and it looks like the sprites in that one are even slightly bigger than the Genesis sprites, so that's one area where it wins out. Or maybe the screen is just stretched and I'm too stupid to notice it. Here's a pic with the PC Engine, Genesis and SNES sprites next to eachother:
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Sound-wise the Genesis version has the issue with scratchy sounding sample playback, although it's far from as pronounced as it usually tends to be, and is otherwise pretty good. SNES samples are cleaner if a bit more muted and filtered, thus less clear. The consensus I've seen in discussion tends to be that people like the music in the Genesis version better.
Near as I can tell, they both play identically, although a more discerning Fatal Fury veteran could probably correct me on that.
Fatal Fury Special
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From left to right - SNES / Sega CD
Video: SNES / Video: Sega CD
This is pretty much both the Turbo and Super equivalent of FF2. Apart from making the endboss Krauser playable, it also adds Ryo from Art of Fighting and reintroduces Duck King from FF1 as playable characters. There was no Genesis cartridge version for this one, but instead JVC ported it to the Sega CD addon.
It's hard to tell at a glance, but it looks like the sprites and backgrounds in the SNES version were redrawn or otherwise edited and slightly improved from Fatal Fury 2. The Sega CD version however is a world of difference. It utilizes the higher Genesis resolution mode of 320x224, and also occupies all of the screen estate without black bars. The character sprites, backgrounds, everything is redrawn to be significantly bigger and more detailed. Not only that, but it's also a lot smarter with how it uses the still more limited color palette, so it looks a lot better than FF2 Gen on that front as well. For some reason the Sega CD version still often lacks the prop elements though.
Sound-wise is where it gets weird though. The SNES version has lower fidelity voices than FF2 and thus more filtered, and in addition to that Takara also used some of the worst implementation of SNES reverb I have ever heard on the system. Everything sounds like it's being reflected in a tin chamber or something. The Sega CD version is, considering the nature of the hardware, even weirder. The music is fine as it's redbook audio recorded directly from the Neo Geo original, and it starts off promising as you hear the clear announcer voice just like the Neo Geo version during the character select screen. Once you get ingame though thinks take a real turn for the worse. The voices/sound effects are actually significantly lower quality than Takara's FF2 Genesis cartridge port. Everything is aliased to hell, and 90% of what you're hearing are the digital aliasing artifacts instead of the actual sounds buried underneath them. I don't know what the hell JVC did here when the Sega CD has much more advanced sample playback capability than the base Genesis.
Samurai Shodown
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From left to right - SNES / Genesis / Sega CD
Video: SNES / Video: Genesis / Video: Sega CD
This is where things get really interesting. You'll notice that the SNES characters are really small. Like, abnormally small even for the system. The Genesis version meanwhile uses the higher resolution, with much bigger sprites and background art. Not only are the sprites big and detailed, but they're pretty well animated too. But to compensate for this, the characters don't seem to have as many unique types of animations. Haohmaru for example doesn't have his jab/thrust medium attack. Instead it's just slashes at different speeds. Logically this would also mean losing gameplay elements, since this also affects stuff like timing and hitboxes. I don't know if the Genesis version lacks anything more gameplay/system-wise since I'm far from a SS power player, but people describe the SNES version as playing more like the Neo Geo original. There's one more important difference here as well in that both the Genesis and SCD ports omit the character Earthquake who is really, really huge and likely goes beyond the hardware sprite limit at that level of fidelity. One can only speculate, but it almost makes sense that Takara deliberately gimped the character sizes in the SNES version to make room for (both in terms of screen and rom size) Earthquake's art assets. So the SNES version gets a unique advantage there. It also has the special count down game mode which isn't found in the other versions.
The sparse traditional Japanese music sounds great on both the SNES and Genesis. But for the few more filled out western-style tracks, it comes closer to the stereotypical average quality on both systems. The SNES version also has the same issues with the sound effects as Fatal Fury Special with the low quality filtered voices and awful reverb. Seems to be a recurring thing with Takara's late-era SNES ports. The Genesis version on the other hand has surprisingly great sample quality. The playback is near crystal clear (apart from the noticeable clipping inherent in the samples, though I don't regard it as distracting at all since typically classic martial arts movie SFX is just as distorted), and the port's SFX is very, very sample heavy. Not just voices but also the impacts, sword slashes, sprinting footsteps, etc. Easily the best sounding fighter on the system.
And third we have JVC's Sega CD port, which is different from the ground up compared to Takara's cartridge version (as opposed to most Sega CD versions of games that also existed on the Genesis). Same resolution but more screen space, with even bigger sprites and even more animation frames thanks to all the CD space, and doesn't omit unique animations like the Genesis does, thus the gameplay remains more arcade accurate. It still doesn't have Earthquake like the SNES version does though. Overall, the graphics are superior to the Genesis version but there are some isolated elements that seemed to be executed better by Takara. For instance you can see the snow dunes in the screenshots are just a simple color gradient on the SCD. And in some cases the color applications stick out as garish compared to Takara's colors. The SCD version also doesn't have the background referee character like the other versions.
And then we have the exact same problem with awful aliased sound effects like in Fatal Fury Special CD. The Genesis sounds are exponentially better, which again just feels ironic considering the gap in sound hardware between the two.
That's about all I'll fit in the OP. There are several more games to compare, and perhaps even those Neo Geo games that SNK didn't develop themselves like World Heroes. I just picked the ones I found most interesting. There's also Art of Fighting which has SNES, Genesis and PC Engine. Art of Fighting 2 is a SNES exclusive port and also Japan-only (Ryuuko no Ken 2). And of course there's Fatal Fury 1.