Board Thread:Theories and Speculation/@comment-25132842-20180312025951/@comment-734582-20180313093729

Indk21, that still doesn't change the fact that Madara was the first to have EMS, or that Izuna willingly gave his eyes. Neither knew that it was going to give him EMS, Izuna did it because he still had good (or reasonable) eyesight and Madara had no real options.

It also doesn't change that the other MS users died to pass on the MS, so none of them could've done the eye exchange trick.

Whether Hagoromo has or hasn't got MS is irrelevant. He doesn't have Tomoe in his Rinnegan so he can't use it with Rinnegan anyway. He also has no siblings to exchange Sharingan with, making EMS unachievable.

Indra doesn't have siblings to exchange sharingan with, so his MS is also irrelevant to the discussion. Though, if he had switched eyes with Ashura then both would have Rinnegan. Not that they ever would agree to such a thing, but it's an interesting thought.