I don’t think Africa wants them.
Then take African Americans, far longer removed from West Africa, and often having European or American Indian ancestors, and place them in Nigeria, Ghana, or Liberia. The locals are culturally conservative and traditionally religious. (Keep in mind that African clergy are usually on the conservative side of Catholicism, Anglicanism, and Methodism.) More prosperous black Americans often do not share these values. Repatriation won't work.