Forgotten Diaspora : Jewish Communities in West Africa and the Making of the Atlantic World by Peter Mark and Josè da Silva Horta discussed the early modern Portuguese-Jewish community in West Africa.
In the late 19th Century, some Sephardic Jews from London migrated to South Africa.
Sephardim, especially from Rhodes and Egypt, established a short-lived community in the Belgian Congo. Later communities were established in South Africa and Rhodesia, now Zimbabwe.
Several African tribes have a tradition of Jewish ancestry. I am not qualified to comment, and do not know if there is a Sephardic component. Probably DNA research will eventually solve the puzzle.
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