Again though, the issue is unlike race or gender, someone doesn't necessarily "look trans" just because they are trans. You could have a transwoman who looked totally like a cis man, totally like a cis woman, or anything in between. You really need to have references within the dialogue or the fact that a character is intended to be trans will fly over the head of many viewers entirely. Basically, inclusion is not enough - there has to be some within-script reference to identity.
Come to think of it, the same thing is true for gay characters in Trek. No one "looks gay" so you need to actually address same-sex relationships in some manner to be inclusive of gay people. Trans is arguably even a bit harder than that however, because of the "show not tell" aspect of storytelling. It's easy to make inferences about sexuality based upon the conduct of characters we see onscreen, but when it comes to the self-professed gender identity of individuals, we often have to be told directly.