Folks are using this as part of the current culture war, which I find to be boring as hell, but I'm a little more interested in the historical figure under discussion.
On the one hand, there is an actual historical document making the claim that this person may have acted in manner consistent with a voluntary change of gender. Of course, back in the day, nobody would have really used the same terminology, let alone with similar implications, so we should be careful about making too many assumptions in either direction.
On the other, whether the document is telling the truth is another curious point to debate. Either it's purely a character assassination that was simply used to spread lies and rumors about a political leader, in which case it could be dismissed, or it was a critical document that was nevertheless spreading more or less true facts, even if the intent behind its writing was to be negative and offensive. In other words, not all rumors are automatically fake. We would need to examine the context and try to find supporting evidence.