I think Leo is male, but is just gender fluid, Harada said it was female around the same time TTT2 dropped which is non canon, plus it's swimsuits in TTT2 can make it either male or female
I view it as male, but can't exactly like "him" like i do Eliot because it's just too complicated, I can't like someone without knowing their true gender first. If Lili was a male for example and was a transgender and Namco never revealed that, I wouldn't be able to like her the way I do now, not because she's a transgender because I don't mind that at all, it's just the whole complexity surrounding her gender with no explanation would be a turn off. Give me Leo with a shirtless option and I'll be convinced, but "his" CG artwork is just too pretty for me to truly believe the gender without valid proof