Everything is in the key words "Potential". I'm sure there will be a fee to move characters, maybe something along the lines of a transfer fee?
But not for nothing that would be really difficult for the GM's to pull off. Unless you just move your lvl or have your lvl cut in half to accommodate the harder grind in 12 Sky 2.
I'm sure you will be able to transfer your AP just like any other Aeria Game.