Azshara is more a Goddess than the Highborn she was.
But she still has her peoples and I'm not sure she dislikes her own planet enough to bring Sargeras wiping everything on earth (and probably under water).
Perhaps I underestimates the madening influence of an Old God, but no Old God would ever ally with a Titan of any sort, even the Dark One if he wants to destroy Azeroth (Old Gods are strongly tied to Azeroth).
I don't see Azshara following orders of anybody, but I don't see her threatening the existence of Azeroth. Seeking revenge on surface dwelling peoples is ok, blowing the all world is not.