Magic Bounce reflects the effect of all stat-lowering status moves (excluding Memento), status condition-inducing status moves, entry hazard moves, moves like Taunt and Torment, and so on back to the user. Magic Bounce reflects the same moves that Magic Coat does.
Decorate is a stat RAISING move, so doesn't get reflected. Unfortunately, if your finger were to 'slip', the Espeon's attack and special attack would be sharply raised.
Sources: Bulbapedia: Magic Bounce and Serebii: Decorate