Perhaps it's related to some ancient ninja art or a hidden power within Naruto himself that gets awakened. In the Naruto universe, there are often latent powers waiting to be discovered. This Hercules - like strength could be tied to his Uzumaki heritage or some long - forgotten jutsu. He may initially struggle with this new power, not knowing how to fully utilize it without causing harm to himself or others. But as the story progresses, he learns to master it.
In some fanfictions, Naruto might obtain super strength through special training. For example, he could be pushed to his limits by a new and powerful mentor who has unique training methods. This could involve extreme physical and mental challenges that force his body and chakra to evolve in ways that give him super strength.
Hercules was the son of Zeus and a mortal woman. Hera, Zeus' wife, was jealous and made his life difficult. He had to perform twelve labors as a form of penance. These labors included slaying the Nemean Lion, capturing the Erymanthian Boar, and cleaning the Augean stables. Through these tasks, he became a great hero.
Naruto would likely become more confident. His Hercules strength would give him an extra boost in battles and he'd start to believe in himself even more. He might also become a bit more reckless at first, thinking his strength can solve all problems.
Well, perhaps the story could revolve around a tournament. Naruto, with his Hercules strength, enters this grand tournament. He has to face opponents who are also extremely powerful. His strength gives him an edge, but he also has to learn to control it. Along the way, he meets new allies and they all have different motives related to the tournament.
Hermione could be the one. With her vast knowledge of the wizarding laws and her sharp intellect, she might dig up some old regulations that prove Harry's right to his money. She would then fight tooth and nail in the wizarding courts or against the goblins at Gringotts to get his money back.
Maybe he discovers some legal loophole in the wizarding world's financial system that allows him to reclaim his inheritance. For example, if there was some improper handling of his family's vault by the goblins at Gringotts, he could use that as a basis to demand his money back.
Well, if we look at the 'Naruto gets his parents back fanfiction', Naruto's character development might take a different turn. Instead of relying solely on his friends and mentors like Iruka and Kakashi, he'd have his parents' direct guidance. His father, Minato, could train him in advanced ninjutsu. His mother, Kushina, could give him all the motherly love and care he was deprived of. This would likely make Naruto more confident and perhaps a bit more relaxed as he wouldn't have that deep - seated longing for family anymore.
Perhaps in the fanfiction, there's a magical object or a powerful spell that can restore his wings. But to find this object or cast the spell, Lucifer has to face many challenges. He might have to team up with some unexpected allies, like a group of angels who initially didn't trust him but later see his determination to get his wings back and decide to help.