This technology does not exist and even if it did it would be pretty ugly.
“This technology does not exist “
And won’t until it’s developed. As for ugly, that depends on details yet to be discovered.
Perhaps not at sea- perhaps somewhere where there is both wind and water, especially water that is not useful for anything else, like sewage plant effluent ( a sewage plant tht makes methane too).
Low power density, intermittent sources are not suitable for main grid, but anywhere that the energy can be added in economically is a boost. Back in the 40’s pumped storage was not feasible, now there are places where they pump water to a tank on a hill and reverse the flow through a generator during peaks.