A translation of a concept art page from Hyrule Historia. Images taken from History of Hyrule’s The Legend of Zelda art anthology.
The Wind Waker Concept Art
Sketches of things that weren’t used in the game, including an underwater scene. Only Lord Jabun, the giant anglerfish, can be met on the back side of Outset Island.
After being pulled out of the water, touching the hook in the underworld will caused you to get pulled up. (Warp)
How about using a fish hook as a warp item?