After a couple years of on and off rewriting, CustomKnightPlus CustomKnight2DTK CustomKnight Super Animation Addon is here!
In it's current state, it supports replacing individual tk2d animations with custom ones originating from user-defined spritesheets! Eventually I want to update it to also include support for normal unity animations.
It is also currently limited to only replacing the Knight's animations, but it can be really easily extended if need be.
Unfortunately, since each animation uses its own spritesheet, this is not very memory-efficient. Luckily, it works with the original custom knight features as well, so you don't have to use every animation.
Requires CustomKnight and FrogCore.
Spritesheets and Json files for original animations can be exported using this
Have fun!