But, I want the peer's changes to be transferred to the host as well so that the "sync" is both ways rather than one.
The plugin doesn't work that way, the host should always be authoritative over changes. In your case when you want the peer to summon an object, what you can do is to have the peer to [action: send message] to the host, then at host, on peer message, you spawn the object on peer behalf. That way the object will be automatically sync over all peers.