#1 Shinsuke Nakamura

Shinsuke Nakamura is another case of a superstar who used to have so much credibility before it was all lost due to his losses. As a babyface, Nakamura was clearly thriving as he was getting solid reactions from the crowd. A heel turn against AJ Styles at Wrestlemania 34 was clearly done so Nakamura could develop a character.
There's no denying that Nakamura has improved as he is getting more comfortable on the mic, but the fans do not seem very interesting during his segments. He doesn't have the same spark as a heel that he used to have as a face. That being said, he really could've been a successful heel if he had taken the WWE Championship away from AJ Styles.
But at the moment, after losing the US Championship to Rusev, it seems as if WWE is going in the direction of having a rematch between Rusev and Nakamura which does indeed make sense. It's unlikely that Nakamura will regain his title as Rusev only won it on the Christmas edition of Smackdown in 2018.
However, after that rivalry is finished, what will be next for Nakamura? He doesn't seem to have a lot to do as a heel, so maybe a turn back to the good side would be beneficial for him? The Artist could keep his cocky character whilst feuding with heels like Daniel Bryan and Randy Orton.
Even as a heel, Nakamura has come across as a likeable character during segments with his funny "Me no speak English" moments that made the WWE Universe burst into laughter. This is the kind of cockiness that we must see from Nakamura as a face. There clearly isn't a better option for a babyface turn that The King of Strong Style himself.