Sasuke could also be a very powerful contender. His Sharingan and Rinnegan give him a lot of combat advantages. If he had Titan abilities, he could use his ocular powers to control and enhance the Titan form. He might be able to see the weak points of his enemies even more clearly in a Titan form and use his lightning - based jutsu more effectively, combined with the brute strength of the Titan.
Writers can give the Female Titan more depth by exploring her emotions. Even though she is a Titan, she can still feel things like anger, fear, or regret. For example, showing her hesitation before attacking a particular character can make her more interesting.
One popular fanfiction idea could be a story where Eren has to team up with the Female Titan against a new, more powerful enemy in the world of Attack on Titan. Maybe they start off as reluctant allies, but as they face challenges together, they begin to understand each other better and develop a unique bond.
The Avengers' abilities would bring a whole new level of combat to the Attack on Titan world. For instance, Iron Man's flight and advanced weaponry would give him an edge in aerial attacks against Titans. Captain America's shield could be used to block Titan attacks and also as a throwing weapon. Thor's hammer would be a powerful melee weapon against the Titans. The characters from Attack on Titan, on the other hand, have their own skills like Eren's Titan - shifting ability. It would be interesting to see how they all work together.
One common theme is the exploration of the blurry line between friend and foe. Since the Female Titan is initially an enemy, fanfictions often delve into whether she can become an ally through her interactions with Armin. For example, Armin might try to convince her to side with the humans.
One good example could be a fanfiction where the Female Titan has an unexpected alliance with the main characters. In this story, she might reveal a hidden side of her nature that was not explored in the original series, like having a moral code that goes against her initial actions as an enemy. This can add a whole new layer of complexity to the character.
The Survey Corps' ODM gear could be used in new and creative ways in a crossover. They could use it to quickly move around the Tokyo Ghoul cityscape, giving them an advantage against the ghouls. Meanwhile, the ghouls' kagune could be used to attack Titans in ways the Attack on Titan characters haven't seen before. For example, a ghoul could use its kagune to slice through a Titan's nape from a distance.
If we consider Goku's Ki blasts and Eren's Titan transformation, they could create a really powerful combination. Goku could use his Ki blasts to weaken a Titan from a distance, and then Eren could finish it off with a powerful Titan - powered attack.
Fem Naruto's superhuman strength, which comes from her chakra - enhanced body, would allow her to take on Titans in close - combat more effectively than the average Attack on Titan character. She could probably leap onto Titans and deliver powerful blows without the need for the ODM gear's blades. Her healing ability, if it exists in the fanfiction, would also be a huge advantage. If a character gets injured during a Titan attack, she could heal them, increasing the survival rate of the soldiers. This would not only change the outcome of individual battles but also the overall morale and strategy of the fight against Titans.
Sasuke's sharingan would give him a huge advantage. He could predict the movements of the Titans, much like he does with his opponents in the Naruto world. His ninjutsu skills, such as fire - style jutsu, could be used to fend off Titans. For example, he could use his fire - style to blind a Titan or create a barrier of fire to keep them at bay. Also, his speed and agility from being a ninja would make him a very effective fighter against the Titans. He could quickly move around the battlefield, avoiding the Titans' attacks and finding their weak points.