None of this is simple. An estimated 170 LGBTI athletes have competed in the Olympics. Gender is often not obvious even without modifications. See:
https://www.thenation.com/article/pe...bti-olympians/

Here's a good story which I remember reading about real time, back when my sport was skiing with a little cycling in the summer. This is another "it's not always obvious" story, the woman who skied like a man:
https://www.skimag.com/uncategorized...hamp-was-a-man.