Well, the idea of Naruto being the son of Kronos and Rhea in a fanfiction is quite wild. It would mean re - imagining Naruto's backstory. He might not be from the Hidden Leaf Village in the same way. His relationships with other characters would also change drastically. Instead of his normal friends and mentors, he could have interactions with characters from Greek mythology. It would be a huge mash - up of two very different fictional worlds.
One possible plot could be Percy's journey to discover his true identity as the son of Kronos and Rhea. He might face challenges from the other gods who fear his power. For example, Zeus could try to stop him from fully realizing his potential. Percy would also have to deal with his own internal struggle. He grew up believing he was Poseidon's son, so this new revelation would shake his world. He could start a quest to find out more about his parents' relationship and what it means for him in the grand scheme of the mythological world.
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.
His character would likely become more complex. He might struggle with the expectations of being the son of powerful deities. His usual ninja values could be challenged as he discovers his new heritage. For instance, he might question his loyalty to the Hidden Leaf if his 'divine' duties call for something different.
Percy would likely become more conflicted. His previous identity as the son of Poseidon shaped his values and actions. But as the son of Kronos and Rhea, he'd have to reevaluate everything. He might become more cautious, as he now represents a more controversial lineage.
His powers would likely be a blend of Kronos' and Rhea's. Kronos was associated with time, so Percy might have some control over time. He could slow it down or speed it up in a small area. Rhea was a mother goddess, so Percy might have a strong connection to nature and the ability to heal. This is different from his original powers as Poseidon's son where he mainly had control over water and could communicate with sea creatures.
Perhaps there are some traitors from the other side. These characters, seeing Kronos' power and potential for victory, switch sides and help him in the war. They might provide valuable information about the enemy's defenses and plans.
In many fanfictions, Percy might use his water powers in a unique way. Maybe he combines his control over water with his sword fighting skills. He could create a giant water vortex to disorient Kronos and then strike with Riptide while Kronos is off - balance.
Some of Kronos' minions, like the monsters he commands, could be antagonists. For instance, the dracaenae. They are always eager to prove themselves to Kronos and might see Percy as competition within Kronos' ranks. They could constantly try to undermine Percy's position and cause trouble for him.
One great Rhea Ripley fanfic is 'Rhea's Ascent'. It beautifully captures her fierce and dominant personality in the ring. The story takes her on a journey of self - discovery outside of the wrestling world while still maintaining her edge.