A lot of the strange looking (oddly square muzzles) and duplicate ponies are from a fanfic called
On A Cross and Arrow. It's an alternate universe story using MLP Fanfic Cliche #243:
Twilight misuses teleport magic and fucks stuff up. The six get transported to an alternate dimension where everyone's genderswitched, and since the normal members of the cast stuck in the alternate world, hijinks ensue.
The author (Conner Cogwork) has written five chapters so far, and I'm enjoying the story quite a bit. It's funny, light-hearted, and generally cute as well as being engagingly written (the other two stories by Conner are definitely worth checking out,
especially this one). CartoonLion draws a lot of art either from or inspired by the male characters in the story, and the male versions of the mane six have names I've seen used across other stories, almost making their names fanon. It's good stuff.