Definitely the potential for epic battles. Picture Goku going up against the Four Emperors all at once. His speed and strength could turn the tides in a battle that the One Piece world has never seen before. Also, his friendship with Luffy could lead to some really heartwarming moments. They both share a love for adventure and fighting strong opponents. And Goku's ability to sense energy could be a game - changer in a world where most rely on observation Haki. It could open up new ways of detecting threats and finding hidden things in the One Piece universe.
One interesting aspect is the character interactions. Characters like Goku and Luffy, who have such different personalities but similar heroic traits, coming together. Goku's pure - hearted love for fighting and Luffy's determination to protect his crew can lead to some great dialogue and storylines. Also, the different settings of the two series being merged. The vast ocean - based world of One Piece and the various planets in Dragon Ball Z create a whole new backdrop for the crossover fanfiction.
Well, a Goku - One Piece crossover fanfiction might involve Goku getting lost in the One Piece universe. He could end up on a random island and befriend Luffy and his crew. Goku would probably be interested in the different Devil Fruits and might even try to use his powers to help them find the One Piece. His fighting skills would also be a great asset during battles against the likes of the Yonko or the World Government's forces.
The character interactions can be really exciting too. Picture Ichigo trying to explain his Soul Reaper duties to the carefree Luffy. Their different personalities create a lot of interesting dialogue and situations. Also, when Ichigo teams up with the Straw Hat crew members like Zoro or Sanji, and they combine their skills in combat. Each has their own fighting style, and seeing them work together against a common foe is thrilling. Moreover, the exploration of new worlds. As Ichigo travels through the One Piece world, he discovers new islands and meets strange creatures, just like the Straw Hats do, and this exploration aspect adds to the excitement.
One possible scenario could be Goku Black using his power to take over a part of the One Piece world. He might try to find the One Piece itself, thinking it could grant him even more power. His dark nature would likely put him at odds with the Straw Hat crew, leading to epic battles.
The combination of powers. For example, seeing Zoro try to fight against a Hollow with his swords in a One Piece - Bleach crossover is fascinating. His swordsmanship could be contrasted with the way Soul Reapers use their zanpakutos.
The new storylines that can be created. For example, a new villain could emerge that requires the combined efforts of both the One Piece and Dragon Ball Z crews to defeat. This could involve battles in different settings from both universes, like fighting on the Grand Line and also in the Hyperbolic Time Chamber. It gives a whole new perspective to the existing story arcs of both series.
Goku would probably be very friendly with Luffy. They both love to fight strong opponents and have a sense of adventure. Goku might be a bit confused by some of the wacky things in the One Piece world like the Devil Fruits at first, but he'd quickly adapt. He'd also likely be impressed by the determination of the other characters like Zoro and Sanji.
The most exciting part is seeing the different power sets interact. Like Thor's lightning powers against Vegeta's energy blasts. It would be a show of raw power and strategy.
The most exciting part is seeing the different power sets interact. Sonic's speed and agility against Goku's super strength and ki blasts make for some really cool battle scenes.
Another plot could involve Naruto using his Rasengan and other jutsu in the One Piece world. His immortality would allow him to explore the mysteries of the One Piece world more freely. For instance, he might join forces with the Straw Hats to uncover the secrets of the Poneglyphs. Since he can't die, he could take more risks in deciphering the dangerous knowledge within them.