The Copts split from the mainstream Christain churches in 451, ostensibly over doctrine etc but apparently there was church power politics involved (which doersn't surprise me). What If after the great schism of 1054 the Western Catholic and/or Eastern Orthodox churches tried get increase their power and influence by trying to re-align with the Coptic churches? Both could say the issue of 451 was just a misunderstanding and find points of commonality to work with.
More important would be the political ramifications of such efforts. The church was tightly integrated with the state, with the Byzantine Emperor being the head of the orthodox chruch and the Pope crowning kings and emperors in the west. So any reasonable attempt for the churches to align themselves with the Coptics would have power political implications. Perhaps European kings would have regular contact with Ethiopia in the 1100s as a result?
More important would be the political ramifications of such efforts. The church was tightly integrated with the state, with the Byzantine Emperor being the head of the orthodox chruch and the Pope crowning kings and emperors in the west. So any reasonable attempt for the churches to align themselves with the Coptics would have power political implications. Perhaps European kings would have regular contact with Ethiopia in the 1100s as a result?