Considering wwx's canonical breeding kink and his general fondness for dubiously safe scientific experiments it is technically within the realm of possibility that a few years post-canon he just invents cultivation hrt and transition surgery by accident.
He just rocks up to a cultivation conference one day 5 months pregnant like "I turned my body into that of a woman! Yeah the boobs too we travel a lot and don't want a wetnurse. I'll reverse it in two years or so." And every single trans person and egg in the culivation world simultaneously sits up and goes "wait what?"
Imperical to understand that wwx still fully identifies as a cis man and does not know trans people exist. He did not know he was gay while actively being in gay love, this man is very smart but he doesn't know shit. Just a few weeks after the conference people start coming over like "hey... that thing you did... can you do that to me?" and he's like damn sure are a lot of dudes who wanna get pregnant. One day a "female" cultivator comes and is like "so you said you're going to reverse it... you think you can do that on a body that's already female? Turn my body into a man's body?" And he just goes well probably, let's find out!! It's so great all these people wanna help him perfect his techniques, isn't it lan zhan?
Years later they run into one of the trans women he first helped and doesn't even recognise her as she's thanking him and after the clarification just goes "wow! haha damn you're even wearing women's clothes! Should I start calling you guniang?" sort of as a joke but she's like yes please and he just says alright nice to see you again ma'am (still doesn't get it)