Combining these two factors, we can derive an explanation to the original question:Nagato couldn't revert the Rinnegan to Sharinganbecause he wasn't the eyes' original owner. Madara displayed certain new and powerful techniques when he received his original eyes. How Nagato got his Rinnegan, Th...
While the extent of its abilities hasn't been revealed to us, we do know that it'll be strong enough to rival the Otsutsuki power, which makes itcomparable to the Rinnegan. Why did Itachi not take his father's eyes? Itachi didn't get the eternal mangekyou because he just didn't want...