I did not know of any ethnically homogeneous units (at least after the war, there were local units in the early USSR), got any sources for that? Sending recruit

I did not know of any ethnically homogeneous units (at least after the war, there were local units in the early USSR), got any sources for that? Sending recruits near their home generally was not allowed though was possible through connections but most people went far away from home and the unit's location had nothing to do with the unit's composition. The US is much more diverse so I don't see how you are going to dodge the issue there. Even sending everyone near home will cause the same issues since the local population is already diverse.