It's not just the insurers but regulations. Although I wonder how much they can skirt around that, for example hiring a bunch of low wage unskilled workers to j

It's not just the insurers but regulations. Although I wonder how much they can skirt around that, for example hiring a bunch of low wage unskilled workers to just sit on the ship doing nothing so it counts as "manned". Perhaps you could have the ship be remote controlled rather than completely autonomous. When something unexpected happened, a person takes over remotely, but otherwise it acts like autopilot. Perhaps the boats could transfer cargo to and from manned boats in international waters to get around local regulations, or even just bring people on board the ship.