Okay, this is in incredibly petty nitpick, but: if you’re writing a fantasy setting with same-sex marriage, a same-sex noble or royal couple typically would not have titles of the same rank – e.g., a prince and a prince, or two queens.
It depends on which system of ranking you use, of course (there are several), but in most systems there’s actually a rule covering this scenario: in the event that a consort’s courtesy title being of the same rank as their spouse’s would potentially create confusion over who holds the title by right and who by courtesy, the consort instead receives the next-highest title on the ladder.
So the husband of a prince would be a duke; the wife of a queen, a princess; and so forth.
(You actually see this rule in practice in the United Kingdom, albeit not in the context of a same-sex marriage; the Queen’s husband is styled a prince because if he were a king, folks might get confused about which of them was the reigning monarch.)
The only common situation where you’d expect to see, for example, two queens in the same marriage is if the reigning monarchs of two different realms married each other – and even then, you’d more likely end up with a complicated arrangement where each queen is technically a princess of the other’s realm in addition to being queen of her own.
You’ve gotta keep it nice and unambiguous who’s actually in charge!