Bl doesn't mean trans love. It means guys falling for guys.
The only one I know as of this moment features a side character that is potentially trans (at least the way I read them) has a character referred to as "Mama" who runs a gay bar. They were my favorite character!
https://www.mangago.zone/read-manga/meguro_to_akino_wa_kizukanai/
I was unsure though if you had meant a story where the two MCs fall in love while one is still presenting as male/sex at birth and then comes out eventually as a trans woman? Or did you mean t4t (which I haven't seen at of yet)?
If that's the case I do think there is a story like that
It's scratching my brain because I DO feel like I've read a story where one of the characters presented before coming out as trans but God Knows I can't remember it?. It was really old and this was definitely a long while ago, the character that was trans was blonde and had long hair, however I do think that the plot was not fluffy. And unfortunately I'm certain the story may have used slurs like "transv*" . However, if you are still interested in it and want to read it and I somehow remember it, I'll come back to this and comment it!
Presented male*
ty smm!! :3
any BLs with actual trans rep that’s not super gross and fetishy!?! Plz send(;_;)