He doesn't need a power-up, what he needs, are power-ups.
Yep, he needs multiple enhancements to reach 50% Sasuke.
100% Sasuke isn't going to be shown in this upcoming fight as he's too powerful for Naruto to handle. Kishimoto will partially restrict him. Sad, I know.
So you have seen the full extent of Naruto powers? Of course he haven't. Don't underestimate Naruto he has sage senjutsu and all of the tail beast chakra. That's a lot of potential.
Having all the tail beast chakra means he has the potential to use all of their unique ability like 3 tail jinchuuriki water mirror jutsu -
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Naruto can us the 9 tails chakra repel the gravity jutsu.
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Naruto has already proven he can use the 5 tail chakra to give him unrivaled strength like the 5 tail jinchuuriki.
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