My first experience with the Fire Emblem games was an attempt to play Awakening that petered out once I collected all the base units in the game and got to the social link romance mechanic. I didn’t find it engaging for several reasons:
1.) There were already a lot of units in that game and the time-travel narrative adding additional units in the form of time travel kids wasn’t great.
2.) I don’t like romances that tie themselves to game mechanics because it end up being a bizarre and uncomfortable pseudo-genetics game.
Fire Emblem: Fates continued that mechanic and also solidified that I wouldn’t touch it the second I found out the deal with Soleil (which @JKDarkSide touched on in their post) along with another really bad decision with the romances in that game that I’m going to put below a cut.
Spoilers | Content warning for incest
In Fire Emblem: Fates, the protagonist you play as is secretly the child of a dragon and a human, but isn’t aware of this and is raised with the understanding that they’re a human. Corrin is adopted into the royal family in Hoshido and raised as the sibling to four other characters. Later on, Corrin gets kidnapped, mind-wiped and adopted into the royal family of Nohr and raised with four other siblings.
The game makes it pretty clear that these characters are Corrin’s family, but that doesn’t make them off-limits for romance supports. One of the characters, Camilla, has a personality that really plays on the ‘big sister’ thing. It’s really gross, and I think it’s reprehensible to imply that incest between siblings is okay if they’re not related by blood.
Considering that the set up for this game is that you’re a teacher at this academy and not a student, and that they’ve given no indication that they’re going to drop the romance supports between the Avatar and the characters, I do not trust where this game is going.