Original characters from what were once MLP fangames
The following is an overview of original characters that took the place of the "Mane Six" characters in My Little Pony: Friendship is Magic fangames that were subsequently made into their own games, specifically Super Lesbian Animal RPG (formerly Super Lesbian Horse RPG) and Them's Fighting Herds (formerly My Little Pony: Fighting is Magic). These games feature their own casts and stories completely independent from MLP, and even the Mane Six inspired characters definitely diverged from their original inspirations, but it's fun to look at how each creative team built on what aspects. None of this artwork is mine, and the vectors are from the respective wikis for these works. The @slarpg art is by @ponett or Bobby Schroeder, from whom you should definitely buy that game (and its soundtrack, and also buy the game to gift for your friends, and just support her she's great), while the art for TFH is by Aaron Tucker.
Fluttershy from MLP:FiM, Melody Amaranth from SLARPG, Pom from TFH
Rainbow Dash from MLP:FiM, Allison Goleta from SLARPG, Tianhuo from TFH
Twilight Sparkle from MLP:FiM, Claire Higsby from SLARPG, Oleander from TFH
Applejack from MLP:FiM, Jodie Caldwell from SLARPG, Arizona from TFH
Pinkie Pie from MLP:FiM, Beverly Piggledy from SLARPG, Paprika from TFH
Rarity from MLP:FiM, Faith Vincent from SLARPG, Velvet Hoofstrongdottr from TFH
The creative teams from both former fan games decided to retain the unicorn species of a unicorn inspired character in each of their Mane Six inspired character rosters: Faith from SLARPG (Rarity) and Oleander from Them’s Fighting Herds (Twilight Sparkle).
The Fluttershy inspired characters, Melody Amaranth from SLARPG and Pom from TFH, have a predominantly pink color scheme with subtle gold accents from accessories. Both of their respective character designers decided to dispense with Fluttershy’s prominent yellow coloration.
Both of the Twilight Sparkle inspired characters, Claire Higsby from SLARPG and Oleander from TFH, are reprimanded for engaging in dangerous magic which invite dark forces into their respective realms. This is a logical convergent evolution from Twilight’s character, but notably not an actual trait of hers as far as I can remember.
Coincidentally, both of the Rarity inspired characters, Faith from SLARPG and Velvet from TFH, have brown fur with a blonde mane/hair despite neither of these being a part of Rarity’s character design.
The most common trait carried over for all of these characters are the eye colors, although this is by no means universal and there are notable exceptions.
In honor of Trans Day of Visibility, it’s worth noting that Melody and Claire from SLARPG are canonically trans, wherein their inspirations Fluttershy and Twilight are trans in my heart.
Hope you enjoyed, sorry in advance for mistakes!