>>115081376I guess maybe if it's done through implication, if the character in question isn't one of the major ones (because if they are, it probably will be something that gets explicitly discussed). Like, the character appears in a photo or flashback and seems to be the opposite gender than in the present day, and/or maybe they're voiced by someone who's actually transgender (like if the character's MTF, the VA is too). So even if they don't explicitly talk about it in the show or aren't allowed to, you'd pick up on it if you're paying attention. I can also see something like the character saying they want to be called by a specific name or use certain pronouns or something.
I guess you could have a trans character, even as the main one, and only say they're trans through supplementary stuff/commentary after the fact, but even though it wouldn't be "hamfisted" that way, I think most people agree that's the cheap lazy bullshit route.