Quote Originally Posted by Ravens_cry View Post
Trans women and cis women are both women, even IRL, but even in a magic universe, there still would be differences in flavour.
That's kind of the point. If I tell a story about Linda and her friend Stacy going to a ski resort, the fact that I'm using words to tell my story (like a TTRPG, and contrasted with a more visual medium like a TV show or video game) means that a lot of details that aren't narratively relevant get left out and offloaded to the listener to fill in. Stacy's hair color and job and trans status tend to get glossed over that way unless they're narratively relevant. (Which, for the benefit of anyone else who comes along browsing this thread, a trans person's ability to pass is far more germane in how people treat them and thus the narrative relevance than the configuration of their genitals is.)

Which gets to the point of how this affects TTRPG settings. If it's no big deal and some combination of magic making passing trivial and/or society absolutely not caring at all, trans status is rarely if ever brought up. It's offloaded to the players to picture, and most players will rarely assume transness unless it's explicitly mentioned. (Books sometimes have it worse where readers will sometimes ignore a minor tidbit in description and then get upset when that tidbit is revealed on screen.)

Which leaves us with three options. Don't mention it because it isn't narratively relevant, in which case players will just fill in whatever and practically none of them will fill in "trans". You can play up realistic problems that trans people might face, but that has high risks of making escapist fantasy unfun for someone who wants to play a trans character and also stands a very high risk of being read as an endorsement of those problems and getting you called out as transphobic. Or you can make an active point of calling out how it's totally cool and nobody in this world cares about trans status, in which case it can come off as forced and kind of twee.

Practically nobody big enough to publish wants to portray realistic hassles because of the risk that someone somewhere will read it as an endorsement of said hassles and cause a major PR headache. That does, however, leave the remaining options as "practical erasure" and "rather twee".