No. And I've never found anyone who can explain what's racist about it.
My definition of racism is denigrating or harming others based on their race.
That various races have different skin tones and facial features is just a dry fact. Nothing racist about acknowledging that British natives look different to Kenyan natives to Indian natives to Japanese natives.
Racism is when you mock them in a nasty way for their differences. Or when you discriminate against them simply because they look different.
But merely dressing up as a person of a different race, and using makeup to complement the look is fine. Of course, as long as it's not done with the intention of mocking.