There soon might be at least one

https://xcancel.com/Highway_30/status/2087700989990121532
Genitalia doesn't determine gender. That's a cis normative fallacy. My trans-affirming doctor told me I can think of my genitalia as 9 inches of clitoris.
Royce White for President
WNBA #LetHerPlay
It seems unlikely that White is actually trans, tweets like this are obviously not serious. The best defense I've seen of this is that right now the WNBA has 0 rules about eligibility, and this will force them to pick some policy. Not sure that that's a particularly strong defense though.