Mass entity AI

Hello there.

So i was prototyping game with wave based system of enemies. Something like they are billions. Very fast i realized that just spawning actors is a rookie mistake. So i looked up and found something called Mass entity. But the documentation is weak and video tutorials are old and only thing that can be spawned is static mesh.

Can this mass entity spawner spawn Actual characters with animations?
Or what is the best way to spawn hundreds of enemies?