That’s actually wrong.
“Intersex” is a general term used for a variety of conditions in which a person is born with a reproductive or sexual anatomy that doesn’t seem to fit the typical definitions of female or male." (ISNA) Intersex people can identify as binary.
Agender is one form of being non-binary. There’s a lot of others. It’s also not a term I’d tend to use in a fantasy game.
As has already been said, cisgender is just the opposite of transgender. Most people are cisgender, Non-binary comes under the transgender label.
I’d admittedly not use any of our terms for describing gender and sexuality in a fantasy game. I think in this case making up your own terminology, using it to slot into your own world, is perfectly acceptable. It may involve a little bit of world-building, just working out how it fits though, how people see things.
I don’t particularly like changeling, but that’s because it’s a word I tend to associate with a child that’s been stolen away by the fae and an impostor left in its place.
Have a read of this thread, particularly the posts after the one I just linked to. Writing Non-binary MCs - Noble Nouns & Other Questions - #21 by SwanMaiden


) So as the game goes along, your ROs are going to get pared down further and further. Each has their own personality, so some may get very upset at you if you win against a friend of theirs in the arena. Ah, the troubles of being Diplomatic… 

