Intersex person here. The specifics of a scene aren't actually all that important! Whatever you get "wrong" can always be 1. fixed later or 2. used to create drama. If the MC says something offensive, it doesn't mean your story automatically sucks, as long as by the end of the story/arc they learn why it was wrong. It's much more important how you see each character on a broader scope, who they are, what they do, etc. The tiny bits, like what they say to each other, that's minutia. The things people will look for are more like "are they smart/cool/tough/etc.".
It's just like characterization has worked for centuries. When everyone is either male or female, black or white, the things that stand out become "are they a nerd, a jock, or a goth? A soldier or a wizard?", and if someone says something like "you can't do _____ because your gender/race/sexuality is ______" or "We can't be friends because you're _____", it's like, "well screw you buddy" or "maybe you're right, damn, society sure can be rough sometimes".
THAT is what your story is about. So just relax, cause you already told us who these people are whether they're intersex/transgender or not. It's less "hello, I have brought unto thee my special person label, hither, let us commence the full explanation of what this label entails", and more like "I'm just tryna get a large shake and fries what do you MEAN my gender is a problem".
Also, like @NickRowler said: listen to people and just paraphrase what they say (with permission). Eventually you'll pick up enough to represent that viewpoint by yourself, but first, you have to learn what the people you want to represent think about their own situations.