Tbf, there's a time and a place for such characters to shred a light on their xenophobia. In a story-driven event, "conflict within party" trope can be interesting if it's something more than throwing a bunch of insults here and there. I don't have much expirience with roleplay in FF, but all the public events I see advertised is something I know as "tavern craft" — bunch of strangers just chilling in a pub6 feet apart cuz they're not gaybasically. That situation rarely calls for unwanted remarks, if at all. Person who goes to a group of strangers just to pick on them or turn the conversation that way either gets ignored or smaked on the head. Same thing applies to characters. There's just not much place for playing Xaela ultra nationalist in a multicultural dance club, for example. At least not with pre-planning. I higly doubt you can DM someone with "Can my char be rasist towards yours for RP reasons?" and get a positive responce. And without consent, that's just gonna ruin other peoples time and probably yours as well.