G3 Rainbow Dash (RAINBOWS DARLING! RAINBOWS!) is Venus Terzo, aka Ranma and Talia Gladys. Come to think of it, her riding the rainbows makes sense.....in the Minerva! MLP fans knew her better as the tomboyPatch.
Cotton Candy and Core 7 Cheerilee isLouise Halevy. So now they were unstable Innovades piloting a monstrous GN-Drive Tau powered Mobile Armor? Well she is also known as Fashion-centric musician pony Melody.
Fashion-centric musician indeed. She's also Barbie...
Wysteria, Minty, Scootaloo, etc became Rarity, Granny Smith, and LUNA, PRINCESS OF THE NIIIIIGHT! Minty is also Derpy, which is prettyfitting.
Kimono, Puzzlemint, and Sweetberry became the GREAT and POWERFUL Trixie.
Brights Brightly became Gilda the Griffon and Spitfire the Wonderbolt.
Starsong and Tiddly-Wink became Diamond Tiara.
Twinkle Twirl, Apple Spice, Daisyjo and Piccolo is Daring-Do.
Tra-La-La is Princess Cadance.
Lily Lightly and Toola-Roola both became Little Strongheart.
What Could Have Been: Fiesta Flair, a character who appeared in the short Pinkie Pie and the Ladybug Jamboree never made it into toy form. Word of God says that due to her Mexican accent, name and symbol there might have been backlash that caused Hasbro to rethink her development.