Magical Leaf Pros:
-Covers Rock
-Can't miss
-Has a good amount of PP
Magical Leaf Cons:
-Not very Powerful
-Grass attacks aren't really needed on Toge
-Definitely not needed since you have Aura Sphere
Psyshock Pros:
-Covers Poison
-Hits on the Physical Side
-Good power
So overall, I'd go with Psyshock. It hits harder, and hits Special Walls which would take the rest of Toge's hits pretty well.
Hope I helped! c: