Are you retconning the one-drop rule? That was a thing of Jim Crow, not the old south.

Sally Hemmings was probably legally white, but whiteness did not free her.

I don’t think there are any pictures of William Ellison, but we know he bought his freedom and then made enough money to purchase slaves. He did not inherit them.

The man who established legal slavery in the colonies was almost certainly of pure African descent: https://medium.com/a-universalist-in-an-identitarian-age/sorry-1619-project-the-first-legal-slaveowner-in-the-american-colonies-was-black-f30d6b4e7254