okay i have a long and complicated heterosexual steve/bucky au but what matters is that the super serum functions essentially like testosterone & steroids. and thus a cis female steve still passes for a man and ends up doing a whole mulan thing with captain america. which she has complicated feelings about but lets not get into that bc the point of this post is her accidentally stolen-valoring like half the identities within the lgbtqia+ community
sam thinks shes a trans woman who's transitioning in the modern era. super reasonable assumption based on what he knows ("captain america" is a man in all the history textbooks, but stevie actively makes an effort to get gendered right off the clock). he fumbles on pronouns like twice while figuring it out and then becomes Steve's Biggest Ally TM and never finds out he is aiding a cis woman with her gender dysphoria and not a trans woman. cool bro move regardless thanks man she needed that
natasha thinks steve is nonbinary and the gender role switching comes from that, because natasha has an insane relationship with her own body+gender and its connection to work. like her role as the femme fatale means she views being a woman as part of her job obligation/title; she views steve's gender situation as similar. she thinks steve is for real actually a man on the job and for real actually a woman off it and this makes so much sense to her.
tony thinks steve & bucky are gay men and refuses to delve into this because he is very worried steve fucked howard and he does not want the details. he makes a lot of mildly homophobic quips that he views as a status of him being progressively accepting (think the "no son of mine wears a skirt........that doesn't match his top!" jokes people made in the 2010s) which steve either totally misses or just views as sexist jokes that she ignores.
thor thinks steve & bucky are lesbians and is very happy for them. he's way more used to the muscular body-builder look on woman so he can easily tell that steve's a gal, but during his early days on earth when he had long hair a lot of people informed him that 'long hair is a girl thing' (it was 2009 after all). so thor assumes any human he sees with long hair is a woman, ergo bucky must be a woman. what a beautiful lesbian partnership. he hopes he gets an invite to the wedding
