Well, there doesn't seem to be a simple way to do that, but if you feel like playing around in the code a bit, I'll direct you to the PokeBattle_Scene script section, where the classes PokeballPlayerSendOutAnimation and PokeballSendOutAnimation are defined. Those animations are played when either the player or the opponent, respectfully, sends out a pokemon into battle. They show ball opening and make the pokemon appear on the field.
Otherwise, perhaps someone has made a custom script somewhere. If you find something interesting, I'd be interested in hearing about it as well.
