The Japanese word for stateless but in the sense that when it comes to the way people of their own ethnicity portray themselves they see themselves as unmarked whereas they other those of different nationalities and ethnicities, which sometimes leads to facial profiling. Anime characters aren’t necessarily white just as The Simpsons aren’t necessarily Asian in that if they’re the default ethnicity, they can’t be stereotyped in any way. Those of other ethnicities tend to be marked, for instance a black person would be stereotyped as oversexed, well-endowed, thuggish or animalistic whereas white people aren’t (in white made media).
I suspect this extends to writing where it’s like how black people would be stereotyped and described as either Mandingos, sambos, mammies, Sapphires, Jezebels, animals (often simian or primate) and thugs. If it were written by a black person, because blackness would be the default here black characters wouldn’t be portrayed that stereotypically unless if that black person has internalised racism and projects it onto women (from my personal experience). If a Nigerian did Nigerian stories, their ethnicity and nationality would be the default and this extends to how ethnicities see each other where a Yoruba sees themselves as unmarked but the Igbo and Hausa are.
This also extends to gender where if men are the default, women are the marked other or for another matter sexuality where if homosexuality’s other, heterosexuality would be default. When it comes to mukokuseki for black people, that’s only when blackness’s made default that we get less stereotypical depictions of black people (though it’s possible to have non-stereotypical black characters in a white-majority or multicultural setting). But it becomes less stereotypical in the sense that if a Nigerian did a black character, that would be the default ethnicity (no special markers needed). It’s not so much of a matter of ethnic and racial differences but rather the perception where if your race’s default it wouldn’t be stereotyped in any way unless if self-hate issues are present (which do exist among some black people).
It’s actually telling with the Milestone comics that the characters are portrayed in a less stereotypical manner than they would be in most other superhero comics at the time, though if it were coming from let’s say a black person (or if that black person’s not that misogynistic and full of self-hate) we’d get a lot of non-stereotypical black characters. When it comes to African comics, this becomes more telling that on one hand they don’t stereotype blackness but on the other hand they’d stereotype African nationalities and ethnicities. Even without comics, this becomes telling in the way they perceive themselves and each other.
A white German wouldn’t see themselves as a stereotype, just the default ethnicity but they’re going to mark Italians, blacks, Turks and Moroccans as the other. It may not always be obvious in writing but it does play off that way, for instance Italians would be stereotyped as lusty, emotional and dark-haired. The more different the ethnicity is, the likelier they are to be othered. The more default the ethnicity is, the less likely they’ll be stereotyped. It does make sense this and why it does deconstruct racism to some extent when it comes to seeing whichever ethnicity’s default.
It may not always be the case but it does make sense that in anime if Japanese people are the default, they wouldn’t be stereotyped in any way but the Chinese and Americans usually get stereotyped and othered in ways they wouldn’t be in their own media and soils. It could apply to any ethnicity and still prove my point right about whichever ethnicity’s predominant.