trying to figure out how that costume's legs work so hard atm
I've worn a fursuit before, they are mega fun. You can breathe through the nose part and can use the mouth piece as well. You see through the eyes with the material used. It's really cool.
As for the legs and other stuff, p sure it's like any other slip on part but heavy and with the need of changing your walking style. I had a friend with gigantic paws and he was exhausted after walking for a short time.