I’ve had multiple straight writers tell me they’re unsure about writing gay (used here as an umbrella term) characters because they either lack that lived experience themselves or don’t want to be unintentionally offensive.
And my initial advice is to do it anyway. Get a sensitive reader (or player if it’s a game) who can help troubleshoot if need be. You can’t make a gay omelet without breaking a few gay eggs~
Honestly I’ve never really understood this line of thinking. Like, if you’re trying to write discrimination into your story and how that affects the characters then sure I get that, but if it’s just the existence of a gay couple- like it’s just a couple with two people of the same gender,. There’s nothing that deep there. They act the same as any other couple.
Again, it doesn’t hurt to get an advisor or talk to people if you’re really digging into it or if there’s a trans character involved, but for the most part I don’t get it. Its not like men need an advisor to help them write women (or if you do, god please just go out and just make female friends.)
Not me, thinking of a number joke rn 
Dropping in some new LGBT dudes with my SIGURD entry (well, at least two out of the three of them are. I am willing to hear out headcanons for the third lmao)
While it is not mentioned in game in my LT game yet (mostly because there isn’t any scene or conversation yet where the topic is discussed, and obviusly writing “hi, im gay” would be dumb XD) the idea is that one of the protagonists is gay and the other is bi.
I may change my mind later but i do not have romance planned for my game for now (other than with pre-existing couples) because by how the plot is in the first demo is (people brainwashed by a curse that makes them think killing is a mercy on the victim) many people in-universe wouldn’t think on trying to pursue romance as a good idea because “what if they happen to be cursed?” I have other characters in mind that could be explicitly LGTB but for now they are concepts in my mind.
Ya, I mean I think also like your posting in FEuniverse, if you post your demo and have stuff there, and say “Hey folks, tell me what you think about the romances in general” people will give feedback if they know that’s something you care about or do it on your projects discord where maybe you can share rough drafts in advance.