Peachy is wearing the ice skates and dress from Snow Angels.
Windy is wearing the shoes and top half of Pony Workout
Baby Glory is wearing the baby version of Pony Workout
Baby Firefly seems to have the hat from Sun and Fun around her neck.
Cherries Jubilee has a hat from one of the parlors on, and some shoes that could be from more than one outfit. If they're harder and stiffer than any of the other shoes, it's from Something Old, Something New. If it's not, it could be from Prima Ballerinas, Flower Darlings, Having a Luau, or Something Old, Something New(there is a soft shoe version).
Moondancer has some legwarmers that could have come from more than one outfit. If they're fuzzy, they're from Prima Ballerinas. If they're not, they're either from Flashprance or one of the pony packs.
The pink shoes could have also come from one of a few outfits judging from the shade I see on the screen. It could be from Party Time, City Kids, or one of the pony packs.
I can't really see what Baby Moondancer is wearing.
Of the two items that are not on the ponies, the pink cape is probably non-pony, and the hat looks like a G3 hat.
There are UK/Euro versions of Snow Angels, Sun and Fun, and Prima Ballerina. If these came from the UK, they might be those. They're basically identical to the USA versions, but they didn't come with a baby set.