I often fly together with my buddy in the X-Plane network.
It isn't really a peer to peer network, but it does work in most aspects.
Height will likely be because 1 of you has sloped runways selected and one has not.
Individual Liveries are not swapped. You'll both end up in the same..
You can't run (or can't start, in some cases) other network apps which "steal" the connection.
These include xsquawkbox, Ivap, Swift, Live Traffic and likely others I don't know...
I hope this helps