In the world of OPM(One punch man) what threat level will Juubito be? And what Monster could defeat him?

Weaker than a rasengan threat.

The only monsters that can pose a threat to him are Boros and Garou, he solos all the other versions effortless outside those 2

He should be able to beat all the monsters tbh, I don't think Boros or Garou can beat him.

Boros was most likely a God level threat considering the criteria, so Jubi Obito should be at the same level. I don't really think he could defeat Boros, but that's irrelevant here.

He would one shot everyone except Saitama.

Then will proceed to hax stomp that overrated trash

Dragon+

God level if u count IT

@akshsarpanch: tatsumaki solos

He would be a beyond God Level Threat