Another plot could involve a prophecy that foretells the coming of a 'Chosen One' who has the power of both the demigods and the Jedi. Percy and Ahsoka are both thought to be possible candidates. They are brought together by the gods and the Jedi Council to figure out which one of them it is. During this time, they face challenges that test not only their physical abilities but also their moral compasses as they come from very different backgrounds but share the same overarching mission.
One possible plot could be that Percy Jackson, being a son of Poseidon, discovers a connection to Aquaman's underwater kingdom. Maybe there's a threat to both the demigod and Atlantean worlds, like an ancient sea monster awakened by dark magic. Percy and Aquaman have to team up, with Percy bringing his demigod skills and knowledge of Greek mythology, and Aquaman his Atlantean powers and understanding of the ocean depths. They would face challenges like underwater mazes, and magical barriers as they try to stop the monster.
Maybe in the fanfiction, Rory is on a mission in Percy's world. Percy, being the son of Poseidon, has a connection to the water which could be useful in a situation where Rory needs to cross a large body of water quickly. They start off as strangers but as they journey together, they discover that their destinies are somehow intertwined. Percy helps Rory understand the nuances of his world, and in return, Rory shows Percy some of her advanced combat techniques.
One possible plot could be that Percy Jackson's world is suddenly invaded by a powerful threat that the demigods alone can't handle. So, Percy and his friends seek the help of the Justice League. The League initially doubts the existence of Greek gods and demigods but soon realizes the seriousness of the situation. They team up, with Percy teaching the heroes about the magic and monsters of his world while they teach him about modern combat and technology. Together, they fight the new threat that combines both magic and advanced weaponry.
Maybe Ahsoka ends up in the Naruto world somehow. She is mistaken for a powerful shinobi at first. Naruto is intrigued by her different look and the strange weapon she wields. They start training together, and Ahsoka's Jedi discipline starts to influence Naruto's more impulsive nature. They find out that there are dark forces at work in both their worlds that are related. So, they decide to travel between the two worlds to stop these forces from causing chaos everywhere.
One possible plot could be that the gods in the Percy Jackson universe sense a great threat from another dimension (the Marvel universe). Percy and his friends are sent to team up with the Avengers. Percy's water powers could be useful in fighting villains like Electro. Annabeth's strategic mind would assist in planning battles against foes like Loki. They all have to learn to work together, with Percy and the Avengers initially having some clashes due to their different ways of handling things.
One possible plot could be that Percy gets lost in a strange dimension and ends up in the Naruto world where he meets Tsunade. Tsunade initially doubts Percy but then realizes his powers when he shows his ability to control water. They then team up to fight a common enemy that is threatening both their worlds.
Maybe in the fanfiction, the zoo is a place where the gods have hidden some of their lost magical artifacts. Percy, being the son of Poseidon, senses a strange water - based magic near the aquarium section. He starts to investigate with Annabeth. Along the way, they face challenges from zoo security (who are unknowingly being influenced by a minor god who doesn't want the artifacts found) and various magical traps set around the exhibits.
A plot could involve Percy being sent to Forks on a quest. He discovers that there's a powerful artifact hidden in the area that could cause chaos if it falls into the wrong hands. The vampires and werewolves in Forks are also after this artifact for their own reasons. Percy has to navigate the complex relationships between these two groups while also trying to keep his true identity as a demigod a secret. Along the way, he forms an unlikely friendship with Jacob, who helps him understand the ways of the werewolves.
One possible plot could be Percy arriving in the DxD world and being mistaken for a new, extremely powerful devil. He then has to navigate the complex politics of the devils while also trying to find a way back home. Along the way, he uses his demigod powers in unique ways against the various threats in the DxD universe.
In this fanfiction, perhaps Gaea discovers a way to use the chakra in Naruto's world to strengthen her own power. She sends her minions to capture ninja who are strong in chakra. Percy Jackson, who has a connection to the spirit world, senses this disturbance and travels to Naruto's world. Naruto and Percy meet and realize they have to work together. They gather allies from both worlds, like Naruto's friends from Konoha and Percy's demigod friends, and fight against Gaea and her forces.