I think the use of large flexible kites is in line with the evolution of AWE (kite-surfing, kite boats, kite ships). In the open sea the conversion by a hydro turbine makes sense, for a continuous production, not to have the generator in flight.
Incidentally SkySails remains a leader in prototyping ship towing with kites, not to mention the average 92 kW achieved with a reeling (yo-yo) flexible kite, by far the greatest performance in AWE. If SkySails is agonizing, I’m afraid the other AWE players are living dead.
Where things get complicated is in the way the tasks are divided up. I could see numerous systems like this dragging a hydro turbine, recharging batteries (for hydrogen, things are more complex). Then these batteries would be collected in a platform like an oil platform. Ships would come from all directions to take away the recharged batteries while leaving batteries to be recharged.