You are having a laugh. He has all the charisma of a dead slug. And pulling ridiculous faces whilst making strange gestures with his fingers is not charismatic. That’s exactly why he isn’t (and in my opinion) will never get over as either a top babyface or heel (and top is a pretty low bar these days). As you said, he didn’t need to talk in Japan where the emphasis is far more on in-ring performance and the people he was in the rung with carried him to those matches because they didn’t indulge the shit that will in the US.
As for Cody, I cannot believe you think he should never turn heel. Anyone who knows anything about wrestling can see that if, and that is a big if, done correctly then turning a beloved babyface heel or hated heel babyface is one of the biggest tools for drawing money (although that isn’t really a thing these days). Just look at Flair, Hogan, Macho Man, Bret, etc. and the reaction they got when they flipped.
As I wrote on another thread, they should be booking Cody to turn on Arn, Tully to pretend to make the save but turn on Arn too and then build a new Horsemen type group with Cody, Hangman and FTR and leave Omega to align with those other dweebs The Young Bucks and Matt Hardy. The makeup of those groups is far more in keeping with their personalities.