Also tried this, actually tried both outer, and SubObject list at the same time. And yes you have a point on that, it should also garbaged in server. For a moment it seemed to me possible since object outers not replicated fully.
Now I was reading the network documents of the Unreal, especially the Owner part. And thought, maybe I’m making a mistake in the first place:
I’m starting to replicate an object in Server_Character1. and let’s say it use NET_CONNECTION_1. Even though I attempt to change its ReplicateList or even set the outer, maybe it just not switching the NET_CONNECTION. That explains why it stays on server, because in server objects are not replicated.