You can assign mirrored collision shapes to animations that have different collision groups, but beyond that I don't think there is a way to get real inheritance like what you want. You still have to assign a single group for the actor to belong.
Generally speaking, I would make a different actor group that more or less acts on behalf of both groups. You have to assign event handlers separately for it, but it is one way to do it and still theoretically keep things coherently organized. As a note, when I have to have multiple collision handlers for different groups, I sometimes have all of them jump to a function call that contains the shared functionality. It makes modifications later much simpler and less error-prone.