Everybody is pointing fingers at Sawa. But Nanba himself said "Our spy on Touto [....] when that boy checks in". The traitor is male.

Finally!!!

Uh, no. There are two traitors. The first one we saw is a male, and that's who he was referring to.

The second is almost certainly Sawa. It can't be Kazumi - he'd never betray the Three Feathers, and it can't be Sento either - he's the hero. So that leaves Banjou (would he be smart enough? Why betray Sento), Misora (why would she help her kidnappers? She hates warfare) and Sawa (who has no alibi here).

You know, if Sento had remembered he had a motorcycle, Akaba might still be alive. :p

That's just how Over-Time translated it. The word used was gender neutral.

Also maybe if Akaba remembered he has a laser on his face that could be used to keep crocodiles at bay.

I have a theory that it is indeed Misora--but that she's totally not aware of it and has not memory of doing any such thing. When she's in her powered state, she remembers nothing afterwards and seems to instinctively protect people close to her. I would not at all be surprised if, after talking to Sento, Stalk figured out how to temporarily trigger such a state and use it to trick her into revealing the information. Stalk is really good at manipulating things like that and I would put nothing past him at this point.

yes that's possible, im sure he'll forgive her and after what he heard what happened to her.

bonjo makes no sense because bloodstark framed him for murder so i dont know why would he make things worse for himself after everything that has happened and he's getting power up from sento, so i dont think it's him.

anything is possible with greese because bloodstark did give him the squash driver so who knows what he's planning to do with him but sento is not really close friends with him and just judging by his reaction is someone really close and it's probably misora.

Wouldn't explain the different voice actress.

Yeah it seens to be a completely different character, now I have no knowledge of the toy guide or upcoming riders etc, just considering the OP itself I would be reallllllly happy with Misora ending up with a driver eventually.

Though perhaps she will get a monster form, that is also possible.

I am expecting Blood Stalk to get a monster form unless he is actually an anti hero doing whatever to give a method to fight whatever the actual villain is, though it is very possible he will just be the main villain in the end.

What different voice actress? I don't recall hearing the traitor speak unless I missed something.