I presume the OP is looking for words, originally names for ethnic groups, that are now used to describe types of people outside these groups. What group is called goyim besides goyim? (“Gentile” I’ll grant you.)
If that is what he is looking for, it doesnt fit very well. "I’m looking for more words to describe people that come from ethnic/religious groups. " is kinda vague and based upon the literal meaning, Goyim fits. Goy just meant “nation” originally, and the connotation has changed to mean “non-Jew”.
Berserk is derived from the Viking berserker warriors
Myrmidon, from the warriors led by Achilles at Troy
Nomad
Turk, in the sense of young Turk, or the derogatory sense of someone who is fierce or brutal
It’s not exactly explicit in the OP, but that’s what all the examples are. Otherwise French, German, Japanese, etc would also fit. I presume he’s looking for something more specific.