Board Thread:Naruto Discussions/@comment-1512913-20170417105433/@comment-25122992-20170417170712

Yeah, that's already an issue, no idea how the EMS eyes would look and work like if they were to return to their natural owner. I'm not completely sure if the EMS would be retained, since it's obviously the combination of two chakra types (from the one who got the eyes transplanted and the one whose eyes are transplanted) which makes it possible to strengthen the MS, both in actual power and in sense that it eliminates the blindness drawback completely. So, it depends if Madara's/Sasuke's chakra would stay in Izuna's/Itachi's eyes even after their return to the latter two, though it's quite likely, I guess. Regarding the design, I think that the original MS pattern of the user always stays as a dominant one, which means that Izuna's/Itachi's (E)MS would reform its design in the way their MS pattern would become a primary pattern, with Madara's/Sasuke's one turning into a supplementary pattern.