Gender is something that is determined in the womb. Transgender people suffer gender dysphoria because of brain-structures formed to work in an individual of the opposite sex, causing a sort of.... Dysphoria. Race is a genetic adaptation to live in a certain region. Generally effects facial-features, melanin-levels, and hair-consistency. Course, there's other stuff, but the point is, it's the result of thousands of years of adaptation and natural selection. The brains of separate races are, however, pretty much indistinguishable. There is no logical or valid reason to think of one's self as belonging to a race they do not. You cannot have a "black-person's brain". Further more, things like blackface and cultural appropriation tend to be looked down upon because, well.... White people DO have a long history of stepping on the cultures of others. It's seen as a bit of a cultural taboo to turn around and try to borrow from/imitate/parody the cultures and racial traits of other ethnicities.