First off, welcome to the board. Second, you do
not want to open the Pandora's Box that is suggesting Ryn should get a vagina. There are only so many ways that Savin can say he has utterly no interest in writing that and there are only so many ways that Ryn can say that
she doesn't want a vagina and they've all been said long ago. She's not 'stuck in transition', she's fine with herself the way she was born. It's the way her sister
treated her that's the problem, not her body.
Evelyn too is quite happy with her current situation and shows precisely no interest in trying to revert her body back to how it used to be.
In general, TFing characters is deliberately restricted to things that are set up from the start because it means
writers only need to account for only so many variables and characters don't devolve into generic sucky garbage.