You literally transmute matter at will, you do not need to fight Killcannon just turn his robot arm into cheese or something. Your nemesis is a villain that you do not need to consider the whole cannot effect living tissue thing for even a second. That is all.
“They’re real people who don’t use logic” is the reply you keep getting but they’re not real people, they’re written characters, the answer is simply that’s how they’re writing it to get a longer fight, anyone with Eves powers in the real world would come to the same conclusion you did