Any reality you do that in is basically useless since you'll be hunted to the ends of the earth if you even return to one. eventually you'll find a world with a being that can permanently kill you no matter how many parallel worlds you to try to hide in.
Thera are infinite universes. Maybe that being could kill some or most but subtracting infinity from infinity is still infinity. There should be a parallel version of me who is nigh-omnipotent, has autopotence or some op ability.
Why would you also think that I'd let them take my power or life? I have parallel existence, I'll just create parallel versions of me and have fun with them. If I had powers and a parallel version of me tried to take it I wouldn't give it to them so I won't literally take their lives or powers just because I can. But it depends on the situation and since we're just parallels we wouldn't have the same point of view.
Ones more problematic, while the other is just too simplistic. Hmm, but if I really had to choose, I’d go with “Singular Reality”. Just because it’s more safer in my “Opinion”.
"Why would you also think that I'd let them take my power or life?" why would you think they'd let you take their power and life? with infinite selves, one of them would either have parralel existence like you or have a immunity to it.
Depends on the situation but there's a very low chance that they'd give it to me. If I persuade them enough they'd give it to me but I know it's not from the heart. And I don't think they'd know how to transfer their abilities, depends on the ability.
I could just summon them instead of mimicking or absorbing their abilities.
Since we're infinite I'll probably not meet that version.
Singular Reality Existence 
Parallel Existence
