There have been some studies on conventional lateralization on cetaceans by marine biologists, that consider functional asymmetries, behavioral preferences and bias, feeding strategies and task efficiency etc... While quite context dependent, it would seem at least toothed whales and blue whales show some signs of right-side dominance, but there is a lot of variation when you factor in water depth, type of foraging activity, acrobatic intensity of rolling underwater... But I think I would go with clockwise for now?