Or do a Harvey/Two-Face from TDK where Dr. Minerva (hmm, wait, both Captain Marvel and WW2 will be featuring female villains named Dr. Minerva?! ) is an ally for the most part before her tragic transformation into Cheetah and have an emotionally charged fight scene at the end.
But the primary villain has to be Circe, right? I mean, unless Steve Trevor is shown only in flashbacks, he needs a witch/god to resurrect him, right?