oh gosh ok this is gonna be difficult to explain so I'm so sorry in advance ANYONE WHO KNOWS FISHING FEEL FREE TO ADD ON TO THIS!!

(not forcing at all on either end but my moot @piscoyt also does mcci a tonne and is so much better at basically everything than me)

so from what I'm aware the vendors are on the third island of every set, like in the menu there's sets of three. Most of the islands have their own "secret" vendor. Islands 3 6 and 9 have the cosmetic vendors and island 4 has the secret frog cosmetic hideout.

On island three you have to climb up the giant tree stump and around the very edge. On almost the opposite side of the rim of the stump, there is a spruce tree and giant mushroom very close to the tree. You jump onto the tree, then onto the mushroom. In the centre of the top of the mushroom there is a scaffolding block. If you hold shift on that you go down it and inside the mushroom is the vendor. Prices range from 30-200 tokens depending on cosmetic rarity

I've only got to island 5 so I have no idea about number 6 and onwards

but etho has to be my highlight sobbing