Ahsoka Tano would be an excellent choice. Their relationship in the Star Wars canon was complex, and in a crossover fanfiction, they could be forced to team up against a greater threat that spans different universes. Another good character could be Doctor Strange. His magic could either clash or complement Darth Maul's Sith powers. Also, Wolverine from the X - Men could be interesting. His healing factor and berserker rage against Darth Maul's lightsaber skills would make for some intense fight scenes.
In crossover fanfiction, Luke Skywalker would be an excellent character to pair with Darth Revan. Luke's journey from a farm boy to a Jedi Master could contrast with Revan's fall and redemption. Another good choice could be Gandalf from The Lord of the Rings. The clash between Gandalf's wisdom and Revan's Sith - influenced knowledge would be interesting. Also, Shepard from Mass Effect could be a great pairing. Their different approaches to leadership and combat would create an engaging story.
Link from 'The Legend of Zelda' would be an excellent character to pair with Escanor. Link is often on a quest to save his world, and Escanor's power could assist him greatly. They could also learn from each other's values. In addition, Aang from 'Avatar: The Last Airbender' could be paired with Escanor. Aang's pacifist nature and Escanor's more battle - ready attitude could lead to some character - development moments. Another character could be Geralt from 'The Witcher'. Geralt's monster - hunting skills and Escanor's raw power could make for a great team in a crossover fanfiction set in a world full of dangerous creatures.
Maybe some of the Jedi who cross paths with Darth Maul, like Qui - Gon Jinn. Their interactions are important in the Star Wars universe. Also, there could be other Sith or dark side characters who are part of Maul's story, perhaps his own apprentices if he has any at some point in the story.
Darth Sidious is an important character. He is Darth Maul's master and plays a crucial role in guiding Maul's actions and training. Another one could be some of the Jedi that Maul encounters during his missions. They are his opponents and their interactions are significant.
If it was a crossover with the Lord of the Rings, Aragorn could be paired with Darth Vader. Aragorn is a noble and skilled warrior, and his leadership skills would contrast with Vader's tyrannical rule. They could start as enemies, but as they learn more about each other's worlds and the threats they face, they might form an uneasy alliance to defeat a greater evil.
In my opinion, they're quite good. They expand on Darth Maul's character and provide some intense action scenes. The writing and illustrations work well together to create an engaging experience.
If it's a crossover with 'Naruto', Naruto Uzumaki would be an interesting character to pair with the Goblin Slayer. Naruto's positive attitude and his powerful ninja skills could complement the Goblin Slayer's more serious and direct fighting style. They could work together to protect a village that is being attacked by goblins. Also, in a crossover with 'One Piece', Luffy could be paired with the Goblin Slayer. Luffy's determination and his ability to lead his crew could be useful when they are facing a large group of goblins.
In a crossover with the DC universe, the Joker could be an interesting character to pair with Tomura Shigaraki. Both are chaotic and have a disregard for life. Their meeting could lead to either a partnership in chaos or a battle for dominance in the criminal underworld.
Asta would be a great character to pair with Yami in a crossover fanfiction. Their mentor - mentee relationship in the original series could be further explored in a new, crossover setting. Another good choice could be Naruto. Naruto's positive attitude and determination could contrast with Yami's more stoic nature, and they could learn a lot from each other in terms of combat and leadership.
Light Yagami from Death Note. It would be a contrast in characters. Mori Jin could find himself in the world of the Death Note and try to stop Light's plans, or they could form an unlikely alliance where Mori Jin tries to change Light's view on justice while also dealing with the power of the Death Note.