I don't think Ame will be giving any of the original 18 leaders any legendaries. Not yet, at least.
It's much more feesible for Adrienn to have a M-Mawile. Save the M-Gardevoir for Radomus round 2
But Scizor was her ace anyways... although a Mega Metagross doesn't look half bad right about now.
But if we face her in the desert, then M-Scizor would be better suited anyway.
Hardy would pretty much be M-Ttar. I'd actually be pretty surprised if it isn't.
I can see Saphira with M-Charizard X, seeing as Solaris would probably keep the M-Garchomp to himself.
Amaria is the only one where I can say I have no clue. Though maybe if I examine the field effects more in-deapth, I might get a better answer than "nothing".
Thought to be completely honest, all I want is to see Terra again in Labradorra and see how that goes.