Havnt done many things with BP client/servers and the like, but generally when programming (logically) you’ll push something to the server, then prompt on the client side to check if its there. And if it is, register it on the client side.
If memory serves their is a Epic tutorial on how to set up multiplayer with clients n the like. Ill try and find it and edit this post for you.
EDIT
Found it lol, its the first one on Youtube that you find after searching Unreal Engine 4 Multiplayer tutorial