Perhaps a plot twist could involve Kronos' essence trying to take over Percy's body. Percy would have to fight against this internal takeover, and in the process, he discovers a way to use Kronos' power for good. This would completely change the dynamics of the Percy Jackson universe as we know it, with Percy becoming a sort of anti - hero figure who uses the power of the enemy to protect his friends and the world.
One possible plot twist could be Percy struggling with his heritage. Since Kronos is a rather evil figure in Greek mythology, Percy might have an inner battle against the dark tendencies that could be associated with his bloodline. He could constantly fight the urge to be cruel or power - hungry like his father was known to be.
One possible plot twist could be that Percy has hidden powers related to Kronos. Since Kronos is a powerful Titan, Percy might have some latent abilities that are similar but not as malevolent. For example, he could have a unique control over time on a small scale, like being able to slow down time briefly in a battle to gain an advantage. Another plot twist could be that the gods initially mistake Percy for being as evil as Kronos due to their relation. This would lead to Percy having to prove his loyalty to the gods and his friends all over again. He would face a lot of distrust and have to overcome many challenges to show that he is not like his 'twin' in nature.
One possible plot could be Percy's discovery of his true parentage as the son of Kronos and Rhea. This could lead to a huge power struggle within the demigod world. Other gods and demigods might fear his potential power and try to either eliminate him or recruit him to their side.
The plot could involve Percy being ostracized by the other demigods due to his relation to Kronos. However, he discovers a prophecy that only he, as the son of Kronos, can fulfill. This prophecy might be about saving the world from a new threat that is related to the Titans in some way. He then has to go on a quest to gather ancient artifacts or gain the trust of certain beings to be able to carry out the prophecy.
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 Naruto facing opposition from both the ninja world and the entities related to Kronos. In the ninja world, they might be suspicious of his newfound powers and origin. And from the side of Kronos' world, there could be those who don't believe he's worthy of being the eldest son. He would then have to prove himself in both realms.
In a fanfiction, Percy could face other demigods who are suspicious of him because of his relation to Kronos. He'd have to prove that he's not going to follow in Kronos' evil footsteps. Maybe he teams up with some unlikely allies, like a child of a minor god, to show his loyalty to the good side.
Yes, there are likely fanfictions out there with this concept. Fanfiction writers often explore alternative storylines and relationships. However, it goes against the canon as in the original 'Percy Jackson' series, Percy is the son of Poseidon. But in the world of fanfiction, anything is possible.
One possible plot twist could be that Percy, as the son of Hades and Hera, discovers a hidden power within him that can control both the underworld and the aspects of Hera's domain like marriage and family. This power could put him in the middle of a great conflict between the gods who are jealous of his unique abilities.
One possible plot twist could be that Percy has to hide his true parentage from his friends at Camp Half - Blood. Since Lycaon was a werewolf - like figure and Lupa is associated with wolves in Roman mythology, Percy might have some wolf - like abilities that he doesn't understand at first. For example, he could have enhanced senses like better smell and hearing, which could make him seem different from other demigods. Another plot twist could be that there are other characters who are secretly aware of his true parentage and are either trying to protect him or use him for their own purposes.