One possible plot could be that Goku and his friends somehow end up in the One Piece world. They meet Luffy and his crew. Goku might be interested in the Devil Fruits and their powers. Luffy, on the other hand, would be excited to see Goku's super strength and ki abilities. They could team up to fight a common enemy like a powerful pirate who has also acquired some sort of dragon ball - like artifacts. This would lead to an epic adventure with both the Saiyans' and the Straw Hats' unique fighting styles combined.
In a Dragon Ball Z and One Piece crossover fanfiction, the plot could involve the Dragon Balls being scattered across the One Piece world. Luffy and his crew, while on their regular adventures, start to notice strange objects that turn out to be Dragon Balls. Goku, sensing the power of the Dragon Balls, travels to that world. There, they face challenges as the villains in the One Piece world also want to use the Dragon Balls' power to achieve their own evil goals. The story would be full of action as the two groups try to protect the Dragon Balls and defeat the villains.
Well, the plot could be centered around a new villain who has the ability to travel between universes. This villain decides to target both the Dragon Ball Z universe and the One Piece universe. He starts by stealing important items from both worlds. Goku and Luffy separately start to investigate these strange disappearances. Eventually, they cross paths and realize that they need to work together. They bring their respective teams along. The Saiyans and the Straw Hats have to learn to fight as one unit. Along the way, they also discover new powers and abilities through their interactions, making for a really exciting and unique fanfiction story.
Well, perhaps the Saiyans in Dragon Ball Z detect the strong energy from the Devil Fruits in One Piece. Vegeta decides to visit the One Piece world to see if he can gain an edge over Goku. Meanwhile, the Straw Hats are dealing with a new threat that seems to be more powerful than any they've faced before. Vegeta initially clashes with the Straw Hats but then realizes they need to work together. They combine their skills, like Goku's Kamehameha and Luffy's Gear Fourth, to take on the big bad.
One possible plot could be that Luffy and his crew are sailing in the Grand Line when they encounter a strange energy. It turns out to be a Dragon Ball. They then have to deal with various villains from both universes trying to get the ball. Maybe Frieza hears about it and teams up with some of the pirates from One Piece. And Goku, sensing the power of the Dragon Ball, also arrives in the One Piece world to help Luffy protect it.
There's also 'Dragon - Pirate Alliance'. This fanfiction delves deep into how the Z - Fighters and the Straw Hat Pirates would form an alliance. It explores the different cultures and fighting styles of the two groups. For example, how Vegeta's pride would interact with Zoro's sense of honor, and how Gohan's intelligence could be used in conjunction with Nami's strategic thinking.
One possible plot could be that Naruto and his friends are facing a powerful new enemy in their world. However, this enemy has some sort of connection to the Dragon Balls. Goku and Vegeta sense the strange energy from Naruto's world and travel there using Instant Transmission. They then team up with Naruto and the others. Naruto is amazed by Goku's strength and ki abilities, while Goku is intrigued by Naruto's chakra and ninja skills. Together, they combine their powers to defeat the common foe.
A cool plot could be a tournament - style crossover. A powerful being from another dimension decides to host a tournament where fighters from Dragon Ball Z and Devilman are invited. Characters like Vegeta and Devilman's friend Akira Fudo would compete. There could be unexpected alliances and rivalries. For example, Piccolo might initially see Devilman as a threat but later realize they have a common goal of protecting their respective worlds. And in the end, they all have to team up against the true evil that the tournament organizer has in store.
One possible plot could be that Thanos has somehow obtained the Dragon Balls. The Avengers team up with Goku and his friends to get the Dragon Balls back and stop Thanos from using them for his evil plans. They have to battle Thanos' forces while also dealing with the different power levels and fighting styles between the two universes.
A plot might involve the Dragon Balls being scattered across the Bleach universe. Ichigo hears rumors about these powerful orbs and starts looking for them. Meanwhile, Goku and his friends also end up in the Bleach world while searching for the Dragon Balls. They meet the Soul Reapers and at first there's some tension. But as they learn more about each other's goals, they work together. The Soul Reapers are fascinated by Goku's power and training methods, and Goku is intrigued by the concept of souls and the afterlife in the Bleach world.
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.
The plot might involve a villain who has the ability to steal both ki and chakra. This forces Goku and Naruto to team up. Goku, with his Super Saiyan forms, provides brute strength, while Naruto, with his various jutsu like Rasengan and his Sage Mode, offers strategic combat skills. They would have to combine their powers in unique ways to defeat this new threat.
Well, it could be about Goku ending up in the One Piece world. Maybe he teams up with Luffy to fight a common enemy. For example, a powerful pirate who has some sort of dragon - like powers similar to the dragons in Dragon Ball. They would combine their unique fighting styles. Goku's energy blasts and Luffy's stretchy attacks would make for an epic showdown against the bad guy.