There could be a young wizard who is just learning his powers. He might be the main character trying to prove himself.
Perhaps a mermaid princess who is on a quest to find a magical pearl that can save her underwater kingdom from a curse. And also a talking fox that acts as a guide for the heroes in the story.
It's hard to say for sure. But perhaps there could be ninjas from a far - off land that we haven't known about before.
There could be a mysterious old wizard who takes Natsu under his wing when he leaves Fairy Tail. This wizard might have knowledge of ancient magics that Natsu is eager to learn.
There might be new characters who are the masters of certain types of magic or skills that haven't been shown much in the story yet. For example, a character who can control time in a very different way from what we've seen before. Or perhaps a character who is a master of illusions and uses that to deceive both enemies and allies. There could also be new characters who are related to the antagonists in some way, like a henchman with a special power that makes him a tough opponent.
It's hard to say exactly. But maybe there will be some foreign soldiers from lands outside the walls that we haven't seen before. They could bring new fighting styles and different perspectives on the Titan problem.
There's no way to be sure yet. But it could be other types of hunters we haven't seen before. Maybe hunters from a far - off land with unique nen abilities.
There could be characters from other regions or factions that we haven't met in the main story yet. Maybe some powerful mages or warriors from a far - off land.
A wandering minstrel - mage. They travel the land singing songs that have magical effects. When they reach Fairy Tail, they are initially seen as a novelty. But during a battle where the guild is being attacked by a horde of shadow creatures, their music - magic proves to be a powerful weapon, and they are welcomed as a new member.
Maybe a smuggler. Smugglers have always been an interesting part of the Star Wars universe. They often get caught up in bigger events and have their own set of skills and motives. So a new smuggler character could be a main character in the new story.
A young dragon slayer from a far - off land who has a unique magic related to the elements that haven't been seen in Fairy Tail before. Maybe his magic is connected to some aspect of the Dragon Cry.
Obviously, Romeo would be the main character. Then there could be characters like Wendy, who is young and has healing magic. Her gentle nature could be an interesting addition to the harem. Another potential character could be Levy, with her intelligence and book - smart magic skills.