Definitely Ben as XLR8 and The Flash. They both have super - speed abilities. XLR8 has his own unique style of running and using his speed, which could be compared and contrasted with The Flash. They could race each other, and then team up to outrun and outmaneuver a villain who also has speed - related powers. Their interactions would be full of energy and banter.
Ben as Ghostfreak and Batman could be a really interesting pair. Ghostfreak has his intangibility and spooky powers. Batman, being a master detective, would be both intrigued and a bit wary of Ghostfreak. Batman could try to figure out the limits of Ghostfreak's powers while Ghostfreak could use his abilities to help Batman in his stealthy operations. It would be a contrast of the spooky and the strategic.
Deadpool and Batman would be really interesting. Batman is all about strategy and discipline, while Deadpool is the complete opposite. Their interactions would be full of tension and humor. Deadpool would constantly try to crack Batman's serious facade with his jokes and antics.
Wonder Woman and Thor would be an exciting pair. Both are powerful warriors from myth - inspired backgrounds. They could exchange stories about their gods and goddesses. In battle, they could combine their strength and weaponry. Wonder Woman's lasso and Thor's hammer could be used in creative ways to defeat enemies. Their personalities are also quite bold, so there would be a lot of banter and mutual respect between them.
I think Spider - Man and Flash would make for a really fun pair. They both have a sense of speed in different ways. Flash has his super - speed, while Spider - Man can move quickly through the city with his webs. They could have races, and Flash could probably teach Spider - Man how to move even faster. Also, their personalities are quite friendly, so they would likely get along well and have some humorous exchanges in the fanfiction.
I think pairing up Batman and Percy Jackson would be really interesting. Batman is all about strategy and preparation, while Percy is more impulsive and relies on his instincts and his powers. Their different approaches could lead to some great moments. Batman could be trying to analyze every situation and come up with a detailed plan, while Percy just jumps into action. And Percy's knowledge of the mythological world could also be something that Batman would find useful in this crossover situation.
It could be Ben himself. His ability to transform into various aliens gives him a unique edge. He can adapt to different situations quickly, which would be fascinating to see when interacting with the Justice League.
I think Naruto would be the most interesting. His boisterous personality and powerful ninja abilities would stand out in the Justice League world.
I think Batman and Robin (from Young Justice) would be really interesting. Batman's brooding and strategic mind against Robin's youthful enthusiasm.
Definitely Thor and Aquaman. Thor is a god from Asgard and has his hammer Mjolnir, while Aquaman is the king of Atlantis and can communicate with sea creatures. They could have a really cool battle in the ocean, with Thor trying to use his lightning powers against Aquaman's trident and his control over the sea.
The most interesting pair might be Naruto and Superman. Superman is an all - powerful being with a strong sense of justice. Naruto also has a strong sense of justice but in a more down - to - earth, ninja - like way. They could have some great discussions about power and responsibility. Also, they could team up in battles, with Superman using his super strength and flight while Naruto uses his ninjutsu. It would be a powerful combination and a great dynamic to explore in the fanfiction.
The interaction between Ben and Robin would be really interesting. Robin is a great strategist and detective, while Ben is more of a brash hero who relies on his alien forms. They could learn a lot from each other. Robin could teach Ben about planning ahead and thinking through his actions, while Ben could show Robin how to be more adaptable in combat by using different alien abilities.