Have you tried
BindPad for additional macro slots? Or
MacroBank for macro profiles? (You could have one profile just for "Raids") I've never heard of an addon that does what you're assking by itself, since I mean, you have to set the group numbers and the icons yourself? I'd really just recommend you use the same icons for every raid, so that way you already have all the macros set up and all you have to do is change names around when that specific person isn't in the raid.
I'm sorry I couldn't be more helpful, but I'll try to keep a look out for you.