8. Scarecrow: Mark Pellegrino
Scarecrow is, of course, the scariest Batman villain ever, and I think that Mark Pellegrino could be a perfect fit for that. Pellegrino is best known for his portrayal of Lucifer on Supernatural, and while he was actually quite hilarious in that role, he had his moments where he was absolutely menacing. I think that he is the right age to play a villain who used to tangle with Batman in his younger days, and with The CW’s knack for reusing the same actors for different shows, it would only make sense for him to end up in the Arrowverse eventually.
I want all the Batman villains to be part of the Batwoman series, even for Bruce Wayne to come back, also Commissioner Gordon, Barbara Gordon, Lucious Fox