Zauz is this timeline's incarnation of Ganondorf.However, instead of trying to kill Link he's biding his time as he can't defeat Bellum due to his ancestor's power being weakened in Wind Waker. So he helps Link defeat it in the hopes that with Bellum out of the way, he can Take Over the World.
The World of the Ocean King is Termina several hundred years later, flooded just like Hyrule was.
Bellum is this timeline's version of Majora.Both Majora and Bellum terrorize a pocket dimension version of Hyrule, and they both also have those creepy yellow eyes. Perhaps an octopus accidentally grabbed Majora's mask after Termina flooded.
Wind Fish and Ocean King are related.Both are whales, both takes you back "to your world" after they awaken, and then turns out Link (and Tetra) were only sleeping for minutes at most. Too much coincidence.