SonOfGod

Really glad to be back, man it felt like a lot of time.

That's why I have classified none under Omnipotence. I personally think the people you listed are just Nigh-Omnipotent or Metapotent. Or in some cases I will just classify them under "Fictional "Omnipotent"". The answer to question is I suppose with fists.

It depends on laws on how time in our universe works. Cause time paradoxes are a headache and no sane man will want to deal with it. Because as you know probably we have no answers to why everything works the way it works i.e like why gravity works the way it does, nobody knows, we just know it does. We till now only have knowledge of how works and deduce/apply it into other situations. So Time Travel to future is possible but to the past, now this will raise a lot of questions. MCU's version too has a lot of inconsistencies(Go watch some vids in YouTube they'll explain better). I personally think ripple effect(Butterfly effect) is most plausible but take my opinion with a grain of salt cause I am not a physicist. But then again we'll probably get some more time travel theories in next decade, so hold your horses in deciding which won't exist.