I am trying to revive a mod that changes the Avian legwear (commoner, worker, fancy, and adventurer, according to the mod folder names) clothing sprites to different ones, but it hasn't been updated since, Beta v. Furious Koala. I HAVE, however, managed to revive another sprite-replacing mod that's been updated since either 2016 or 2018, but the sprites from that mod didn't work, so I revived said mod by swapping the "humanoid" folder in Better Avians for the mod one. So, all I'm trying to say here is, that I want to revive an old mod, but don't know how. Beware, though, the mod I am trying to update is (this is the only "rule-friendly" way I can put it) *facepalm*... l o o d. (and you will have to extract the folder)
I dont really understand what you are having trouble with. The files you posted above should be all you need, other than maybe a metadata file for the mod
You need to update the folder names to include the dash and keep it all lowercase. avian-adventurer avian-commoner avian-fancy avian-worker