For black people in places like the US and South Africa "passing" is a real phenomenon where one's cultural designation in a race hierarchy is inconsistent with their racial lineage. The psychological trauma of passing is real, and comes at the cost of having to deny family, culture, and the trauma of occupying a position of privilege while those in your race of origin continue to suffer.

"Passing" definitely exists, but it's not the same type of condition as the body dysphorias we've been discussing. The person you're describing isn't suffering due to a disconnect between an internal sense of what their skin color should be and the actual shade of their skin color. They're making a conscious choice to present as belonging to one cultural grouping that doesn't correspond to their internal sense of self - which is a little different than having a body that doesn't correspond to one's internal sense of self. Both can cause psychological suffering, but they're different things.

Being forced to choose between "staying true" to your culture of origin or the economic/social security that comes from "joining" the dominant majority culture - whether through passing or assimilation - can certainly cause a great deal of pain. But it's not generally itself considered a psychological condition (though the traumas associated with it can certainly give rise to psychological conditions or disorders, such as depression or anxiety).