I know a lot of people like to prove it otherwise but, if any empirical evidence actually supports some of the ideas like the early ancient Egyptians were black, the African presence in the Americas that predated the European, of black civilization in East Asia or the Black Athena idea. Some notable scholars that come to mind are John Henrik Clarke, Ivan van Sertima, and Martin Bernal.
the African presence in the Americas that predated the European
There is no evidence for this. You can read more about it and related theories in our FAQ, though please do follow up with more specific questions you might have.
I don't at all consider myself to be a "Afrocentric", I do know Egyptian history very well. One of the problems and disconnects with Afrocentrism is proving someone is "black" or of "African" ancestry is weird because we're all kinda African but no one is black.
Race is fake. You should recognize the difference between phenotype and genotype, one is traceable through DNA the other is represented by features we see. Race is a creation of phenotype.
So immediately we're putting our conditioned understanding of peoples of different colors into a system that's only existed within the last 300yrs the way we know it.
If you want concrete reasoning you should read Martin Bernal's Black Athena which you state. I don't believe Ancient Egyptians were "black" that's made up nonsense but they were African, Egypt is on the continent of Africa. They've alluded to where their origins reside, this also correlates with a few things:
We know the Ancient Egyptians differed from the present Egyptians. Modern Egyptians don't practice the same religions as the ancients or know of the ancient's philosophies or decipher hieroglyphics for that matter? It's because Egypt went through centuries of foreign conquest after it had been established for 3K years (Assyrians, Persians, Greeks then Rome). Then something happened around 639CE that migrated Arabs into the area and later, Turkey and the Ottoman empire which brings us to now.
Now to Afrocentrism
Black people aren't entirely crazy for thinking Egyptians were "black" in the way we use the word today on phenotype alone:
In the Louvre Museum in Paris there's paintings of Amenhotep III taken from his tomb. Many peoples have seen these themselves and would conclude that if that guy was alive in 1960's Alabama he'd have to sit at the back of the bus.
So it gets tricky. They look blackish... or something to the sort. Are we using the one drop rule? Or just skin tone? Are we using femur and skull sizes well then in that case you have this from Constantin François de Chassebœuf, comte de Volney.
Black people have reason to be reluctant to the classifications of scholars, historically speaking there's been a pervasive inclination of academia to deny African achievement. Case and point would be the discovery of Great Zimbabwe, when archeologist found the ruins Cecil Rhodes & crew immediately thought they couldn't have been of African origins. They came up with crazy theories to explain how it got there.