Pirates: Steel Chain Fingers

Neither in the manga nor in the animation has there ever been a situation where a person with an ability was splashed by sea water or was unable to use his ability and was completely powerless.

Symptoms of weakness occur only when the condition "at least a substantial portion of the body is submerged in water" is met.

Otherwise, in a naval battle, a random wave of water hits the side of the ship, and the splash can directly wipe out the capable ones on the deck.

Don't think that people who are capable of being overcome by the sky can't touch it at all when you see "sea water". Only falling into the sea is considered a threat to those who are capable.