This went down about as well as I expected...

I was about to say the game doesn't really specify one way or another, but there's a few instances. Thancred is shown to be interested in women (early on, at least) tho could just be for info-gathering, Alphinaud too apparently? Urianger seemed pretty into Moenbryda, female characters are not allowed relationships lest the nerds riot actually Krile and Mikoto (who?) express interest in male characters so there's that...

On the flip side besides the WoLsexual characters (Haurchefant, Alisaie, Aymeric??) I can only think of the Wanderer's Palace (Hard) duo, a Hyur and a Miqo'te both male... which, yeah there's barely anything...

Hopefully Ryne and Gaia, as reasonably major characters, can change that but that's probably not happening