It's nearly impossible to tell a Japanese person from a northern Chinese person by appearance. Genetic studies show they're extremely closely related which is probably why. It's much easier to tell the same northern Chinese person from a southern Chinese person which will be obvious by skin color alone. Going by names, I can spot the one Japanese author of a paper with ten East Asian authors on the first try. That's the real trick.
But speaking as a Celt, you can fuck right off and stay out of our whisky. 8)