“Not a member of the African diaspora” is a non-racist way to rename whiteness.
It’s too wordy to be a good handle, but it is a reasonable meaning.
A test I’d apply to any alternative word for white is whether it captures me, a white of African descent. My grandmother was born in Africa*. Her parents or grandparents were from France. My father, her son, was born in Africa. His father was from Belgium. I was born in the US. So I am African-American but the one-drop rule would name me white.
There is also the smell test for alternative words. Is it violent or supremacist, like “master race” or “Aryan”?
“Non-diaspora” would pass both these tests.