There is this fairly recent Pokémon Episode in which the three girls appear in a TV show, performing as costumed Super Heroines, including typical Henshin Scenes (No Nudity involved, though) and Sound Effects. Still, it was different enough so that it could also serve as Pretty Cure/Wedding Peach/Doremi etc. Parody/Expy.
Judging by the campy dialogue, OTOH, it sounded like they're doing a hidden, effortly-produced Commercial for Soft Drinks.
P. S.: Bonus Points in this case for actually changing their usual hairstyles & colours!