Uhh...maybe I'm misinterpreting something, but I think you're making more of this than it really is.
Someone who was born in Korea but adopted by a typical US-centric family is going to act like .... a US citizen.
Sometimes such people don't give a fuck about where they were born and their birth families. Sometimes they do. Sometimes they face racism and cultural misunderstanding. Sometimes they don't. Sometimes they want to build up their ethnic heritage. Sometimes they don't give a flying fuck. You build the character as you would any other character: you look at their childhood and how it affected them, and what challenges they might have faced and how it affects them in the present.
As for how people react to them, unless you're building npcs that is strictly dependent on other players.
Zhi grew up as the daughter of a second-generation Limsa Lominsa miqo'te, until she became a street kid. She acts like what she is: a product of the street who did not manage to escape the criminal lifestyle. Some traditional moon kitties have been put off by the way she acts.
Someone who was born in Korea but adopted by a typical US-centric family is going to act like .... a US citizen.
Sometimes such people don't give a fuck about where they were born and their birth families. Sometimes they do. Sometimes they face racism and cultural misunderstanding. Sometimes they don't. Sometimes they want to build up their ethnic heritage. Sometimes they don't give a flying fuck. You build the character as you would any other character: you look at their childhood and how it affected them, and what challenges they might have faced and how it affects them in the present.
As for how people react to them, unless you're building npcs that is strictly dependent on other players.
Zhi grew up as the daughter of a second-generation Limsa Lominsa miqo'te, until she became a street kid. She acts like what she is: a product of the street who did not manage to escape the criminal lifestyle. Some traditional moon kitties have been put off by the way she acts.