One of the best books DC ever published was Captain Carrot and His Amazing Zoo Crew by Scott Shaw! and Roy Thomas.
In the book, we met animal versions of the mainstream DC universe on Earth C-Minus.
If we had gotten to see other DC animal characters, this is my take on what some of them may have looked like.
Swamp Thing, Lobo, Plastic Man, Big Barda, Mr. Miracle, Captain Atom, The Creeper