Percy would likely become more withdrawn at first. The trauma of being the sole survivor would take a toll on his usually outgoing and confident personality. He might start to question his own abilities and whether he could have done more to save his friends.
He would probably become more somber. The loss of all his friends would make him less carefree. His sense of humor might still be there, but it would be tinged with sadness.
It could involve Percy dealing with the guilt of being the sole survivor. Maybe he has to face the families of the fallen comrades and explain what happened. He might also be on a journey to find out if there was a deeper reason for him being the only one left alive.
He would likely be more cautious and distrustful. Since he's being raised by a monster, he may not have the same sense of heroism and justice that the normal Percy has. He might see the world as a more dangerous place where only the strong survive.
Percy's character could become more self - aware. Seeing his past self would make him reflect on how far he's come. He might realize that he's grown more confident and capable over time.
Percy's character would likely become more in tune with nature. He'd be more reserved perhaps, as he grows up in an all - female group. His sense of honor might be more shaped by Artemis' values, such as protecting the weak and the natural world.
His character could develop in a way that he becomes more powerful. Since Kronos is a very powerful being, Percy might inherit some latent power. But he would have to learn to control it. He would also become more empathetic towards the Titans in a sense, as he realizes that Kronos is his brother. This could lead to him trying to find a middle ground between the Titans and the gods, which would be a major shift in his character from just being a defender of the gods.
Percy's character would develop in many ways. Firstly, he'd gain a deeper understanding of the politics among the gods. This would make him more calculating and strategic. He'd also become more empathetic towards the gods' viewpoints, even if he doesn't always agree. His relationships with his old friends would change too. He might not be able to be as carefree with them as he used to be. Instead, he'd have to consider how his actions as king affect them and the entire demigod community. Moreover, his sense of responsibility would expand far beyond just protecting his friends and family to safeguarding the entire divine and mortal worlds.
Percy would likely become more confident, given the immense power he's gained from absorbing Ouranos. He might also become more solitary, as he tries to understand and control this new power within him.
Percy would likely become more diplomatic. As Hera's husband, he'd have to deal with all kinds of divine politics, so he'd learn to be more tactful in his words and actions.
Percy's character would likely become more versatile. He'd start to incorporate Apollo's traits like confidence and a love for the arts. His power set might expand to include things like healing, which is associated with Apollo. He'd also become more in tune with the sun and light, which could change his overall perspective on things.