I don't think this Scallop is particularly fun.

Hover, frankly, cannot fight in water now. If it is to succeed, either claymore or scalpel must be buffed, perhaps both. Perhaps scalpel's missiles could pierce water, even if they cannot target into it - making it better against floating units (you could call it a targeting issue). Perhaps claymore could have major knockback, pushing floating units out of range (though it would then perhaps be too good, and the only unit spammed).

Scallop trashes any unit with its range or less in water, and units that only shoot above water cannot hit it reliably enough.

My current go-to recommendation is the scalpel missiles can go into the water, but only target units above it. I think it will work out well with the current Scallop.