I know that exact feeling, like you just stumbled across a rattlesnake, tho in my case it has more to do with white people generically than certain features and seems to only activate with about a third of white people I meet in general

I'm fairly positive its a subset of that general feeling people get when they encounter sociopaths and psychopaths who aren't masking properly, fashion, posture, tone of voice, the way folks make eye contact, the brain is tipped off in any number of ways that the vibe is fucked

Also people IN GENERAL tend to overestimate their ability to conceal their hostility, and if you're feeling it with every white person you meet, then you may be living in a locale where self-segregation is a conscious community phenomenon and that can be quite dangerous