Cross Epoch is a one-shot Japanese manga collaboration by Eiichiro Oda and Akira Toriyama. It’s a crossover between their respective masterpieces, One Piece and Dragon Ball.
The story does not involve epic battles but consists of short scenes in which the characters, usually one of each series in pairs, interact together. Even if the characters here have roles different from usual they remain anyway faithful to themselves.
In this manga Chopper and Krillin are conductors of a roller coaster
Nami and Bulma are thieves
Sanji and Master Roshi are police officers
Vegeta(here with Nico Robin, Trunks and Usopp) has horns and is the captain of a pirate crew
Piccolo is a swordsman as Zoro
At last, here is Buggy with Emperor Pilaf