This is just an idea—but instead of character transfers, what if the Isle of Siptah map were directly integrated into Exile Lands for players who own the DLC?
Imagine traveling to Buccaneer Bay, paying an NPC some coin, and being transported to Siptah as if you were entering a dungeon. A cinematic animation or loading screen could play—perhaps a Viking ship or pirate vessel caught in a violent storm, eventually shipwrecking. Then you spawn on the shores of the Isle of Siptah, ready to explore and farm.
It would be really cool if each Exile Lands map had its own connected Siptah instance, allowing players to travel back and forth to gather resources, discover recipes, and progress—without ever needing to switch servers.