I have a 12 core Mac Pro set as prime for Roon, and a macbook air with 4TB external storage for travel. Can I duplicate my primary Roon library on the macbook?
You can only have one Core active per licence, but as many remotes and endpoints as your hardware permits. You would have to transfer the Core between the Pro and the Air. If you make the Air the Core and take it away, then the Pro will not work until the Core is back on the same network.
If you do decide to swap Cores, make sure to backup your databases on each Core. You can then swap them in and out when you change Core back and avoid a lot of re-analysing.
You could also get a second licence and have two Cores, I haven’t seen anyone report doing that though.