My best guess… they’re in the middle of some sort of musical montage about the upcoming games, trying on different outfits, and then Twilight interrupts them in the middle of it.
@FanOfMostEverything
Pinkie rounded up a cow, and Sunset Shimmer is gonna turn the hide into a football for AJ right after she fixes the cracks Fluttershy’s helmet with a welding torch but Pinkie gets arrested by Rainbow Dash because the cow belonged to Rarity’s ranch.
…. well considering the shot right before this scitwi was holding that amulet which seems to be detecting magical energy. They most likely hiding the magical pony ears and tails.