I don't think that Hinako is gay, she is most likely bi.
Considering her reaction to the mere thought of being loved by a man, even one she considers pretty much perfect, I highly doubt that.
Agreed, she's as gay as can be, she just doesn't know it yet.
I'm not convinced she doesn't know. I mean, it's possible she didn't know, but she definitely is aware that she has romantic feelings for Satou. She barely paused when Subaru suggested it, and is definitely checking Satou for interest the next day.