I only know of one that lets you do it at blueprint compile time since that’s the how custom k2 nodes can act as macros to replace themselves with a different set of nodes. But that requires a compiler context variable that you don’t have (and only creates them temporarily to boot).
I wouldn’t be surprised if there isn’t one that let you do it dynamically like you’re trying to do. Not that there isn’t one, but I’ve never had reason to find it.