Who might Percy Jackson meet if he goes back in time in the fanfiction?

He might meet a new teacher who is secretly a minor god or goddess in disguise.

Percy might meet an old enemy who has somehow been resurrected or changed in the future. This enemy could be more powerful and have a new plan to take over the world or destroy the demigods. Or he could meet a group of time - traveling demigods from an even further future who are trying to fix something in Percy's future that has gone wrong.

He could also meet some minor nymphs or spirits that inhabit the island. These beings might be curious about Percy's return and have their own stories to tell. For instance, there could be a water nymph who has some knowledge about a prophecy related to Percy and his return to Ogygia. Or a spirit that has been observing the changes in Ogygia since Percy last left and can give him some insights on what has been going on in his absence.

He might meet his former classmates who have changed a lot since he left. Maybe some new students who are intrigued by his reputation.

He could meet his old teachers again. They might be surprised to see him back after his long absence.

Percy might run into Loki. Loki is known for his trickery. He could either befriend Percy for his own devious plans or try to deceive him. Percy, being used to dealing with tricky situations in his own world, would have to be on his guard against Loki's schemes.

He could meet other demigods from different pantheons. Since it's a different world, there might be demigods associated with gods that Percy has never heard of before.

He might meet a younger version of Alfred. Alfred has always been an important figure in the Wayne family and Damian could learn a lot from him, or even try to give him some hints about the future. Also, he could run into a younger Commissioner Gordon. Their interactions could be really interesting as Gordon is such an important ally of Batman.

There's a good chance he'll meet the goddess Athena. Since Percy has a connection to the world of the gods, and Athena is known for her wisdom and strategic thinking, she could offer Percy some valuable advice. Maybe she'd help him navigate the complex social and political situations in ancient Greece or teach him some new ways to use his demigod powers.

He might meet some talented witches and wizards. Maybe there would be a student who is an expert in magical beasts and they could share stories about their encounters with strange creatures.