What could be the plot of a 'Percy Jackson x Tsunade' fanfiction?

Yes, there are some out there. You can start by looking on popular fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'Percy Jackson x Tsunade' in their search bars, and you might find some interesting stories written by fans who like to combine these two different fictional universes.

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.

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.

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.

Perhaps in this fanfiction, the Olympians are concerned about the growing power of the superheroes. Percy is sent as a liaison to Nick Fury. Fury, initially skeptical, soon realizes Percy can be a great asset. Together, they work to maintain peace between the two very different worlds of demigods and superheroes.

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.

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.

A possible plot might be that Percy accidentally stumbles upon Aphrodite's secret garden, a place where she goes to contemplate love. Aphrodite, instead of being angry, is intrigued by Percy's intrusion. She starts to visit Percy in his dreams, slowly drawing him into her world of love. Percy is both fascinated and scared by this new experience. As they interact more, Percy discovers that Aphrodite has a deeper side to her, and they gradually fall in love. However, their relationship is threatened by the prophecy that Percy has to fulfill and the jealousy of some of Aphrodite's children.

One possible plot could be that Percy Jackson, with his water - controlling powers, gets transported to the Marvel universe. He meets Black Widow during a mission where they are both after a powerful artifact that has ties to both the Greek mythology in Percy's world and some secret Hydra project in the Marvel world. They start off as distrustful allies but gradually learn to work together and respect each other's skills.

One plot idea could be that Percy, after all his adventures, finds solace and a different kind of love in Hestia's hearth. Hestia could be a guiding light for him in a more emotional and personal way.