For Supernatural, Constance Welch, Pamela Barnes, and the Sandy McCoy iteration of the crossroads demon are played by mixed-race actresses. Do they count? There's also Sam's friend and that cop from 1x01, one of the dead boys from 1x02, the cop from 1x05, one of the shapeshifter-disguised-itself-as guys from 1x06, Lori's friend from 1x07, Missouri's customer from 1x09, the surviving cop from 1x10, the editor from 1x13, the landlady from 1x16, the dead girl from 1x17, the doctor from 2x01, and that is where I ran out of steam for Characters Count Wiki but I know there's more.

I will find the names for all of these. Must sleep first, though. (Tracking down all the other chromatic characters in the series will take more effort and there's no way I can get any significant progress before Remix starts, though, too many episodes to go through.)