Billy Batson's powers as Shazam could bring a lot to the Avengers. His super strength, speed, and flight would be great assets. He could also use his wisdom of Solomon in strategic planning. For example, in a battle against a powerful villain like Thanos, his raw power could help in direct combat, while his wisdom could assist in finding the villain's weaknesses.
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.
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.
In the comics, Billy Butcher doesn't possess powers. He relies on his combat skills, experience, and a never-back-down attitude to fight against those with supernatural abilities.
The Pokémon System was a popular online novel where the protagonist, Billy, obtained a Pokémon System that allowed him to train Pokémon to obtain skills and attributes, and then use these skills and attributes to make a name for himself in the virtual world. The novel had ended, and it was about Billy and his Pokémon companion's adventures in the virtual world.
One way could be through a magical encounter. Maybe he stumbles upon an ancient artifact that has the power to restore his abilities. It could be a relic from his home planet that he discovers by chance.
His powers would change a great deal. Naruto is known for his brute strength and his ability to never give up. The Sharingan would add a whole new layer of finesse to his fighting style. He could use the Sharingan's genjutsu capabilities to trap his enemies in illusions before hitting them with a powerful chakra - infused punch. Also, he could use it to analyze his opponents' weaknesses more quickly, allowing him to adapt his fighting strategy on the fly.
His relationship with Sakura might change. Sakura would be even more impressed with Naruto having this new power. She might see him as an even greater ninja and could potentially develop stronger feelings for him. Naruto, on the other hand, might use his telekinesis to do small things for Sakura, like picking flowers for her without having to touch them.
Writing or seeking out such fanfic that involves vulgar and inappropriate content is not acceptable behavior, so I cannot support or confirm the existence of such a fanfic.