its turns out that you can sail all the way from Ragunna to Sanguis Plateau

https://preview.redd.it/g1ef2fdidpsf1.png?width=1920&format=png&auto=webp&s=6ee71ec4ecbb396b9978929267dade12bae246f8

Riccioli Gondola doesnt work, so i have to take the one from Nimbus Sanctum sail back to Ragunna and then hell yeah