Well, it could have completely changed the course of the story. Maybe he would have used his powers more strategically or made different choices that affected the outcome.
If Eren knew about his powers earlier in fanfiction, it might have led to him being more confident or overconfident. It could also have affected his relationships with other characters and their reactions to him.
Yes, there might be. The Naruto and Attack on Titan fandoms are both huge, and fans often like to cross over their favorite characters in fanfiction. So it's quite possible to find Eren - from Attack on Titan - in Naruto fanfiction. However, it may not be as common as fanfictions within each respective universe.
In a more AU (Alternate Universe) setting, they could be in a world where the titan threat doesn't exist. They are just two normal people in a small town. Eren has been in love with Mikasa for a long time but was too shy to act. One day, during a local festival, he finally gathers the courage to kiss her under the twinkling lights.
A fanfic with dark Naruto and Mokuton could have Naruto using his powers to create a labyrinth of wooden mazes. He could trap his enemies in there and play cruel games with them. His dark side would make him enjoy the suffering of others. And his Mokuton would be an extension of this cruel nature. The story could then be about how his former friends and allies try to break through his defenses, both physical in the form of the mazes and mental in terms of getting through to the real Naruto inside the dark shell.
Eventually, Eren might start to investigate the reasons behind Mikasa's betrayal. If he discovers that there are more complex factors at play, like she was forced or there was a misunderstanding, he could feel a mix of guilt for his initial reaction and relief that their relationship wasn't as broken as he thought. However, if he finds out that she truly betrayed him out of her own will, he might become even more determined to carry out his plans, whatever they are, without her.
Another way Ichigo could get his powers back in fanfiction is through a magical or spiritual artifact. Maybe he discovers an ancient sword or a talisman that has the ability to restore his lost powers. This could be part of a grander plot where he has to go on a quest to find this item, facing various challenges and enemies along the way. During this journey, he might also learn more about the true nature of his powers and how they are connected to the overall 'Bleach' universe.
Maybe he doesn't fully understand his powers yet. Tony Stark is a scientific genius, but new powers might be beyond his current understanding. He could be worried that if he reveals them too soon, he won't be able to control them properly and might cause harm. So, he chooses to hide them while he studies and figures them out.
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.
One possibility is that Percy trains his powers with the help of his friends. They could create special scenarios or obstacles for him to overcome, which in turn helps him to develop his powers further. His powers could also start to evolve in unexpected ways during this training process.
One unique way in fanfiction is that he gets his powers from a virtual reality experiment. The scientists were trying to simulate the powers of a spider in a digital realm, but something went wrong and Peter Parker, who was a test subject, got the powers transferred to him in the real world.
One consequence could be Percy becoming an outcast among his fellow demigods. Since his powers now come from Kronos, they might see him as a threat or a corrupted being.