But Naruto knows about the weakness underneath susanoo. I dont know if the yata mirrors protection goes down that far, but it doesnt seem like it.Itachi wins for two reasons: 1) Naruto has no sealing techniques, meaning no matter how good he is, Itachi simply has to wait him out. And 2) Itachi has the Totsuka Blade and Yata Mirror, meaning he can reflect any attack Naruto throws and instantly seal him with one swipe.
Now if Naruto had a partner with a sealing technique...
Naruto can send a clone underground with a RS and distract Itachi until the clone pops out of the ground inside susanoo. This way, naruto can beat an alive itachi, but saying edo itachi makes it that naruto is guaranteed to lose because he has no sealing techs that we know of