mammal hiveminds in fiction run the gamut from individuals who are constantly connected telepathically yet retain recognizable individuality to groups where the individual is only a meat robot. the gender identity of the "members" of any given hivemind is different in each depiction, each fictional universe's rules.

you're perfectly welcome to identify with a concept of gender that is impossible to explain to others but you aren't the sole arbiter of what hiveminds are or what writers decide about the genders of members of hiveminds.

and for completeness, multiple personalities in one mind is also not usually what anyone means when we say "hive mind" but even if we do for the sake of avoiding a tangent i don't care about, the gender identities of people in that situation are varied as well.