My friend Is doing a collab called Lavender Heart. It's an anthro transformation story where a group of friends get turned into anthro versions of the mane 6 and other ponies. Trixie is revealed in the story, starting out as a rival to Twilight (a la Boast Busters and later Magic Duel).

Anyone want to help collab as Trixie or Starlight Glimmer, Rarity, or any background character (anthro version) feel free to pm me or Skalltrox Defiance Knight (who is writing for Twilight Sparkle).