So if Kishi let Itachi do the hand signs for the edo release like Madara an came back to life i think he could have gotten Sasuke blind set of eye and awaken EMS. Itachi with his full body Susano'o an in great health would be a problem for Madara,Rinnegan or not in my honest opinion.
Itachi would neg. Unlike Sasuke, his eyes are perfect to awaken the Rinnegan just like Izuna's were. Madara would get fodderized if Itachi possessed the Rinnegan that had Indra + Ashura's chakra.
Healthy Itachi could have done.
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Even Blind Itachi with SM would neg Madara. Rinnegan Itachi is just too OP and also Itachi is immune to back stabs, front stabs, side stabs etc...