There isn't much of anything that I'm aware of. There's lots about the roles of men and women (especially in the context of marriage), and plenty about sexuality, but not so much trans people.
Based purely on scripture, there's no reason that trans issues should be so touchy in the church. I think it has less to do with being faithful to Jesus and more about people using scripture out of context to justify bigoted behavior, because trans people make them uncomfortable.
Unfortunately, the church has reacted poorly and unfaithfully on pretty much all the LGBTQ+ issues.
I mean it's all bs but Paul says that it's unnatural for men to have long hair so... I don't think Pauline Christianity would have been very trans-inclusive
That's not something that stuck with me, probably because I'm a woman, and those things aren't that important to me. A quick search says the Torah says not to let the hair grow wild but to trim it. I'd have to dig deeper, into the Jewish learning sites. Thanks for this!