Dawn of a Royal Day!

Ash and friends arrive in a town where they find out that one of the last contests before the Grand Festival is going to be held. Since Dawn already has her fifth ribbon, however, she decides not to participate. As they're moving on, a woman comes up to them and asks them to follow, bringing them to a princess by the name of Salvia. Surprisingly, Salvia looks as if she could be Dawn's identical twin, and because of this, the former asks Dawn if she could take her place as princess for one day so that she could participate in the Pokémon Contest. How will Dawn react to this extraordinary request?