Oh, sure, but you could do that while allowing a safe distance. You do want it _close_ for ease of interconnection, but a safety gap should be feasible (for instance, offshore wind sometimes has a shore battery installation, but it's generally on the shore, not actually out with the turbines.)
That's probably for the cost of building a battery platform and also the actual tie in to the wider grid will be on land anyways so you're still building it close to the tie in point, the generation is just lightly distributed due to the nature of offshore wind.
From looking at satellite, they have some batteries right next to power plant and some further away in facility. I don't know why they put some nearby when they have space further away.