I don't see why not. They are using a Batman villain, Anarchy, in Arrow. Roy Harper will reappear again, and his alias is Jason who is working as a mechanic. And, its been teased that they will be using the Red Hood. In the Batman comics, Jason Todd used to steal cars and had a thing for cars.
Toyman/Winslow Shott is in Supergirl. He is Kara's tech gadget friend. Ra's al Ghul, Nyssa were if I remember originally Batman characters but then expanded to be included in other titles. Even Talia al Ghul ran Lex Corp when Lex became President.