>>213090116Most northeast asians share a lot of common ancestry/DNA. Including Koreans and Japanese who trace their ancestry to China.
https://pmc.ncbi.nlm.nih.gov/articles/PMC3087676/
>"These findings are consistent with linguistic, archaeological and historical evidence, which suggest that the direct ancestors of Koreans were proto-Koreans who inhabited the northeastern region of China and the Korean Peninsula during the Neolithic (8,000-1,000 BC) and Bronze (1,500-400 BC) Ages."You can kind of tell them apart but there's too much DNA in common and they share too much recent ancestry.
It only gets easier once you move into South China/Vietnam/SEA where there's the SEA DNA that allows you to identify them from northeast asians