They effectively play an animated character live and voice it as they perform it's facial expressions.
On the subject of Japanese gender changes, a most interesting one is played by a Japanese female artist who plays a male character that looks like a female once again. — this artist has a particular habit of creating male characters that look as though they be female.
https://www.youtube.com/watch?v=aRkO-V29fFw&ab_channel=Spiri...
Why do we even really care about real world appearance, appearance is something that we have very little control over and if we've accidentally created something in the internet that allows folks to escape their appearance can't we just celebrate it?
We seem to be accepting that gender identification and body dysmorphia are both real things that people deal with and this meta-society where you can look however you please is probably a really helpful outlet for those who don't like how people judge their appearance from day-to-day - I think it's important that we preserve this freedom and try and ascend beyond judging people by their meat-bags.
Want to influence people? Use faceapp to change yourself into a face people feel good seeing (pretty girl strikes the correct neurons in majority of viewers). In the best case limit everybody does this and hopefully it stops being effective. Worst case every influencing person does this anyway?