Thani's information on supports come from early development, so they aren't fully developed, but apparently Female Byleth has more gay supports than Male. There are some "camp characters" and openly LGBT+ characters. Edgelgard is bisexual. Dorothea and Mercedes are LGBT as well. Apparently some LGBT characters are spoilery. M!Byleth can romance Lynhart.

This is the main reason I hope Thani's source is wrong.

I'm all for representation, but the LGBT+ community isn't nearly as pervasive/concentrated enough to make the majority of the cast being bi believable. At that point if feels like they're just shoving it in your face, like they're saying "take that straight people" which is both childish and detrimental to their cause.