I think passing pointers to globals or directly to data stored in external files might result in some memory errors, but I'm not sure since I haven't tried it.
You could also pass an argument that tells what sprite set the animation should use. The function then could call another function which loads the tile set needed from an external data file (if you don't have an external file already, there's not much need for a DLL because that's the stuff that can be stored outside the real program the easiest way).