And sure, I have had the occasional pipeline with a sissy wanting to explore their trans leaning self. Thats cool too but rare. I think if gender is more of a factor outside of the kink that's different and should be explored with your trans community.
Saw a little snippet of podcast how sissification is a degrading term to feminity. A sissy is a cross dressing man, not a trans woman, not a woman. So lets keep it a degrading term.