I have an idea. Bring a friend with no stuff on a dummy raft and you bring the main one. Then if you want to sail somewhere, get your friend to sail in front of you so if the Leedsichthys finds finds you, it'll go for the dummy raft.
So legitimately honey pacifies this whale. If you have a raft base or something and you have honey to spare you can throw honey into the water and it will stop attacking you. Check the wiki if you don’t believe me. Make sure other people see this
In this tutorial I will Show you how to easily trap a Leedsichthy.
Before I start with the tutorial i want to say that there are 2 ways to trap him. The 1st way is that you build a giant square inside the water where he can fit in and the 2nd war is that you leed him inside the "river" of the Red Obelisk and close both entrys to the river. Just follow those steps:
1) surch for a Leedsichthy and remember where he is (they often spawn near Herbivore Island)
2) Go to the Bottom of the ocean and surch for a Ammonite. When you find one let him bite you.
3) go to the leedsichthy and lead him inside your giant square or the river of the Red obelisk and close up all entrys.
4) kill all fishes except the Leedsichthy
5) Enjoy scrabing of his prime fish meat (he wont get aggro as long as you dont hit him)