Miss Martian from Young Justice could be a great focus. Her powers of telepathy and shape - shifting make her a formidable opponent. Also, her experiences as a young hero trying to fit in and be accepted, especially when facing the more established Justice League, can lead to some really interesting character development and plot twists.
Superboy is often a popular choice. His complex origin story, being a clone of Superman, gives a lot of room for exploration in fanfiction. Writers can delve into his identity issues and how he fits in with both the Young Justice team and in relation to the Justice League.
Definitely Superboy from Young Justice. His super strength would be crucial in direct confrontations with the Injustice League. Also, Lex Luthor from the Injustice League as he is a mastermind and his plans would drive much of the conflict.
I think Batman and Robin (from Young Justice) would be really interesting. Batman's brooding and strategic mind against Robin's youthful enthusiasm.
Flash is always an interesting character. His super - speed gives him a unique perspective and allows for some really cool action scenes. You can explore how he perceives time differently during battles.
Batman is often a very popular character. In fanfiction, he can be portrayed in different ways, like a more nurturing mentor figure to the Young Justice team or as a master strategist leading the Justice League in complex battles.
It's hard to say who would win. The Justice League has more experience and raw power. But Young Justice is more unpredictable and often thinks outside the box. If it was a straight - up fight, the Justice League might have the edge in terms of power levels. However, Young Justice could use their youth and creativity to find weaknesses in the Justice League's more traditional fighting styles.
Superboy is really popular. His struggle with his identity as a clone and his place in the world makes for great fanfiction. Writers can explore his relationships with other characters like Superman, who he has a complex connection to, and his friends in the Young Justice team.
Definitely Superman and the Red Ranger. Superman is known for his incredible strength and moral compass, and the Red Ranger is often the leader of the Power Rangers. Their leadership styles could either clash or complement each other. Also, Batman and the Blue Ranger would be fascinating. Batman's detective skills and strategic planning could be contrasted with the Blue Ranger's more technical skills in handling the Ranger technology.
Definitely Kid Flash. He has a connection to both Young Justice and The Flash. His relationship with The Flash could be explored further, like how he feels about being in the shadow of the more famous speedster while also being a key member of Young Justice. And his powers could be a great asset in the crossover, as he can keep up with The Flash in terms of speed to a certain extent.
Superboy would be interesting as well. He's constantly trying to figure out his place in the world, and in a homefront fanfiction, he could be exploring his humanity further. He might get involved in community service activities to understand normal people better, which could lead to some really cool character development.