I think "nicht vertraut" or "not familiar" (unfamiliar) is the best translation, but I'm not certain - I don't know German well.

I'm not sure.

If I say "Dating russian girls makes me cringe because I feel unfamiliar." then would this make sense for English speakers? I'm not sure if one can use it the way "unvertraut" can be used in German. I'm not a native English speaker as you probably can see, I speak German. Many English speakers don't always understand what I mean in English, because my English is poor and I speak like a third-grader.

I have found a word "unconversant", but it's way too Latin and I have a phobia of Latin words. Although "unfamiliar" is Latin too. May be the best translation would be "unconversant", not "unfamiliar"?