Can you create instances of an actor?

When trying to procedurally generate a world, made of 10000’s of actors. Is there anyway to make those actors an instance? I would all actors of the same object to be instances of each other, then If I decide to interact with that instance, delete that instance, and spawn the real independent actor in its position without the player knowing.

For fun, I am making a minecraft style game (as a break from my normal project), each block is an actor, but spawning those blocks kills performance, and hogs up all my memory.

100,000 grass block instances of a static mesh = 20fps on my crappy laptop
100,000 grass block Actors = 1-2 fps on crappy laptop.

Did you ever find out how to do this?