So I say this game where one thing that got me facepalming was an obviously Caucasian portrait of a King of Abyssinia, modern day Ethiopia and Somalia.
Well, maybe it would be fun just to see how that could happen.
So here is the challenge. Start POD from 1190, the third Crusade. Get these landmarks.
By 1220, have at least 3,000 European family units go into Abyssinia. A family unit is defined by a male female pair that will have a surviving kid. Since childbirth death is common, there is going to need to be more than that number. They can be civilians, or soldiers along with significant others.
By 1530, have a white-looking Miaphysite (Coptic Christian or some call it Oritental Orthodox which has nothing to do with Eastern Orthodox) monarch on the Abyssinian throne who is a decentdant of Yekuno Amlak. The local royal family must not be displaced forcefully (so I guess that means our newcomers need to strike it rich to make them appealable marriage candidates to marry into nobility and later royalty). I think one needs 7 out of 8 great grandparents to light skinned to have light skin oneself, but I don't remember the melain genes of the top of my head.
By 1620, have the Coptic Christians and Catholic Christians not at each other's throats. This can be by getting along or isolation. The Abyssinian Kingdom must be more prosperous than its OTL counterpart.
Or maybe 1190 is too late to hit any of these. The Third Crusade seems militarily doomed.