I don't see any way it could. There's no 'hell' and no 'nephalem' and no 'lord of hell' or anything.
Minimal overlap, which in no way, shape or form links both franchises together to the point that "if something goes for one, it also goes for the other". Diablo wizard and WoW mage are not interconnected at all.Class abilities do not overlap between the two franchises?
Medivh wasn't just an "elite mage". He was given more powers than your average mage. By your logic, "void magic" are one of the powers of the warrior class. Because Garrosh, 'empowered by the Y'shaarj heart' or not, was still a warrior, nonetheless.Doesn't matter if he's an elite Mage, he's a Mage nonetheless.
That's an old game and much has been retconned. No mage in the history of Warcraft after WCII ever displayed the ability to shoot lightning.Not to mention the WC2 Mage that you completely ignored.