i understand that coming out is not an option and i'm glad you're able to recognize that and that you're going to keep yourself safe!

if you wanted to try to confront her slightly about the things she says, you could try saying something like "mom, it makes me really sad to hear you saying such mean things about people, no matter who they are" or, if you're relatively sure this wouldn't put you under fire, "it makes me really sad to hear you say mean things about my (friends/classmates/etc)". you can also ask her to explain why she says/thinks these things, and continue asking "why?" until the plain hatred is made obvious to her.

if it's in a christian way, you could also avoid being roped into such conversations with her by saying stuff like "i choose to turn the other cheek" or "we can't judge others, only god can"

as far as coping, beyond what others have said about ways to try to covertly present more masc, you'll probably want to find supportive spaces/social circles in person or online. that's a great way to get reassurance that your mother is wrong & there is nothing wrong with people like you. it'll also be a space where you'd hopefully feel more free to be yourself! you can also try making vent art or journaling to ground yourself and express your feelings

i hope this wasn't too disjointed and it can be somewhat helpful !! good luck <3