The plot could involve Gaea creating a rift between the Naruto and Percy Jackson universes. This rift is causing problems in both worlds, like strange creatures appearing in Naruto's world that are from Percy Jackson's world and vice versa. Naruto and Percy are chosen by some prophetic force to close the rift and stop Gaea. Along their journey, they face many challenges, including battles with Gaea's hybrid creations that combine the powers and creatures from both universes.
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.
In a 'Percy Jackson Husband of Gaea' fanfiction plot, perhaps there's a prophecy that foretells of Percy being united with Gaea. Percy initially resists, but as events unfold, he realizes that there's more to Gaea than just the evil entity he thought she was. They could start to work together to bring about a new order in the world of the gods and demigods. Along the way, they face opposition from other gods who see their union as a threat. Percy has to balance his loyalty to his friends and his new - found relationship with Gaea, all while trying to understand his role in this strange new world order.
In this fanfiction, there could be a prophecy about a lemon that will either save or doom the world in the face of Gaea's threat. Percy Jackson is tasked with finding this lemon. Along the way, he meets various characters who either help or hinder his quest. When he finally finds the lemon, he has to make a difficult choice. If he gives the lemon to Gaea, she might spare some of his friends but would gain enough power to cause great destruction. If he destroys the lemon, he risks angering Gaea and starting a full - scale war. So, he has to find a third option that no one has thought of before.
One possible plot could be Percy's discovery of his true parentage. He might struggle with the implications of being the son of two powerful primordial deities. For example, he could face a conflict between the forces associated with Ouranos and Gaea. This could lead to him having to make difficult choices about which side to support, if any. And he may also have to deal with the reactions of his friends and the other demigods who might view him differently now.
One possible plot could be Percy discovering his true parentage as Gaea's eldest son and struggling with the implications. He might have to face the wrath of the other demigods who see Gaea as an enemy. For example, he could try to convince his friends like Annabeth that he is still on their side despite his newfound origin.
The plot could involve Percy's journey to discover the true meaning of being the son of Gaea and Pontus. He could be on a quest to find out more about his parents' realms and how they interact with the world of the demigods. Along the way, he may encounter mythical creatures that are related to Gaea and Pontus, and he has to either fight them or make peace with them. There could also be a sub - plot about Percy's relationships with his friends at Camp Half - Blood, as they struggle to accept this new side of him.
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.
One idea could be a crossover where Naruto's world is somehow connected to Percy Jackson's, and Gaea's influence seeps into both. For example, Gaea could manipulate the natural elements in Naruto's world, like the forests and mountains, similar to how she does in Percy Jackson's world. And Naruto, with his ninja skills, teams up with Percy to fight against Gaea's chaos.
A common theme is redemption. Many fanfictions explore the idea of Gaea being redeemed through her interaction with Percy. Since Percy is often seen as a symbol of hope and goodness in the original series, his influence on Gaea can be a way to show that even the most malevolent beings can change.
The plot might involve Black Widow being sent on a mission to investigate some strange happenings that turn out to be related to the magic and mythology of Percy Jackson's world. Percy gets involved because he has knowledge of these things. They start off at odds but as they uncover the mystery together, they start to respect and rely on each other. Their different backgrounds - Percy from a world of gods and monsters and Black Widow from a world of superheroes and villains - would create a lot of room for interesting character development and plot twists.