Pony Royale was a short-lived line produced by Razor USA in 2012. I’m aware of 12 ponies (one for each birthstone – there is a “gem” mounted on each pony’s forehead), plus a playset with a bonus horse; there were also individual hair fashion packs.
Each pony came with “Mix-It-Up Fashion” pieces fit by plugs into holes on the pony’s body. Each had a saddle blanket, “saddlette” (the saddle clip that goes on top), bustle (tulle over the tail), crown, and brush. Some had an ankle cuff. Ponies were packaged wearing one set of “Change-It-Up Hair”, and came with an additional set to swap out.
There were also hair and accessory packs, at least six named sets plus color variations.
The designer, Heather Fonseca, has some production sketches posted on her website.
These are ponies I’ve collected used in lots, and am matching them up with their accessories the best I can based on eBay pictures. Feel free to contact me with any corrections/additions.
Rosie (Garnet):
Lily (Amethyst)
Misty (Aquamarine):
Diamond (Diamond):
Sienna (Emerald):
Lavender (Alexandrite):
Starfire (Ruby):
Brooke (Peridot):
Sky (Sapphire):
Harmony (Pink Zircona)
“Rainbow Harmony” came with certain editions of the Dressing Carousel playset. I have two Harmonys and accessories from both versions; the base pony looks to be the same, except one has a code number printed on her hoof. Otherwise the two versions just have different hair and accessories.
Sunburst (Topaz):
Dewdrop (Blue Zircona):
Change-It-Up hair packs
Flower Fantasy (pink with tinsel, 4 glitter stick-on flowers): 
Heart ‘n Soul
Blossom Beauty
Mix-It-Up fashion packs
Prance Along the Beach
Party at the Palace
Chasing Butterflies
Unidentified bits:
Dressing Carousel (some boxes came with Rainbow Harmony pony)
The box shows the playset mounted with hair and accessories, but it only came with two skirts (as called on the box; these pieces were termed bustles with the ponies themselves) that doubled as curtains. They’re not shown clearly on the box; one appears to be red, and I do have this red one that seems to be different than any that came with the ponies:
Stock images:
