I've never heard of trolls in mythology without horns, but really, that's not the stupidest biological sticking point in this story.
Why the hell do trolls have biological sexes, let alone social gender identifiers? They reproduce by having genetic fluid from any troll mix with genetic fluid from any other troll, using a third party agency to do it, and compatibility is based on having strong enough feels for each other. Why would trolls dress or act in a manner consistent with human sexes? As stupid and tumblrist-pandering as that is, what makes it stupider is there's a part in one of the games where this happens:
You can pretend to misunderstand all you want, but we've talked about this before and I know you're smarter about this than you let on. We were raised in what was a formally "matriarchal society", which has always been used as a shield to downplay clear instances of female oppression and obfuscate the relevance of gender roles, particularly where they're weighted against females. But anyone who's looked at our society more honestly can see that while, yes, it is superficially observed as a matriarchy on a fuschia-down basis, on a practical level all of the enforcement and political power governing most classes was delegated to the higher CIPs, which were generally male-dominated castes. They got to control the agenda and dictate the social conventions, and anyone who dared to object or bring light to this could always be countered with "Hey! Matriarchy! End of discussion.
So yeah, the troll society where no troll is biologically either sex ever has not only male and female trolls, but is male-dominated in spite of having an empress.