So I played with some mods and saw that the after I've slaughter mojave outpost I still welcomed to macarran camp. I thought it was a problem with mods but then I uninstall all mods (and already tried reinstall the whole game) the situation is still the same. And I got vivified karma for NCR with some ranger came after me. Same with Legion faction.
Is this normal ?

And after I complete Black Mountain quest by fixing Rhonda and let tabitha and that robot wander off, all super mutants in that area turned to neutral to me ?

Its normal to have hit squads on you when your vilified with a certain faction. Tabatha and Neil probably said you're alright after finding a non-violent solution to Black Mountain.

Really, unless you want to kill them all, I prefer having the supermutants not coming after me. On my first play thru I killed her, second time I saved her. I used Black Mountain to get around to get to some quests later. It went much easier the second time. since they all would gang up on you if you dropped in.

Man...its common sense if you kill NCR Camp you get reputation of The Legion...and if you kill a Legion Camp you get reputation from the NCR...thats why you are still Neutral :fallout: