Reigen does have powers in the manga, but they are often presented in a more subtle and unique way. His abilities might not be straightforward combat skills but could involve manipulation or perception.
In the manga, Reigen doesn't have powers. His charm and appeal come from his down-to-earth nature and the way he navigates the supernatural world without relying on extraordinary abilities.
Reigen survives throughout the manga. The story doesn't involve his death. The plot focuses on his adventures and interactions without that tragic event.
Perhaps he gets a power related to mind control. This would allow him to influence the actions of his enemies or even make them fight among themselves. He could also gain a power that lets him absorb the powers of his defeated foes. So, every time he defeats an enemy, he becomes stronger by adding their powers to his own arsenal.
Obviously, Dipper is the main character as the title implies. His sister Mabel is often included too. She might react in various ways to Dipper getting powers, like being excited or a bit jealous. Wendy is also a common character. She could be a source of support or a love interest for Dipper in some fanfictions.
In this fanfiction, Robin might get powers as a result of a genetic mutation triggered by a rare chemical. These powers could include enhanced speed and the ability to see in the dark. He initially hides his powers from the team because he's afraid of how they'll react. But when a dangerous situation arises where his powers could be the key to victory, he reveals them and they all work together to defeat the enemy and accept his new status.
Well, it could be that Naruto gets some kind of elemental powers from the comet. Maybe the comet is associated with a new, rare element that Naruto can then manipulate. This new power could give him an edge in battles, as his opponents would be unfamiliar with it. He could use it in creative ways, like combining it with his existing jutsu to create even more powerful attacks.