Naruto System in One Piece - Chapter 5: A Rank Ninjutsu

All Ewan Giacometti wants from his wife is a son. But after three years of unhappiness and disillusionment, Athena Moore is ready to leave her ice cold husband. When she finally asks for a divorce, Ewan’s cunny ‘best friend’ frames her, driving her out of the city. Now, Ewan is left to confront his true feelings about his wife, whom he had married under mysterious circumstances, especially when she returns from exile a changed woman.

With the Legendary Mechanic System, I transmigrated to Marvel Universe to be Dr. Zola’s assistant.

With Mechanical Force Analysis, I can learn every black technology.

Winter Soldier’s arm? I built a better one for you.

Iron Man’s armor? I already made it a decade earlier.

Doc Ock’s tentacles? I am the one who provided core technology.

Hulk’s mutation? Sorry, I was there and got hit by the radiation too.

As for a certain purple potato, can he collect all Infinity Stones?

……

However, I only had one simple ultimate dream. That is to go home…

- Description from Novelupdates

Returning to the Mysterious Era features a boy who can time-travel back to the past using old relics. The twist? He’s stuck in the body of the relic’s owner.After a near-death experience, Cassius unlocks his ability to travel to the past in the body of Li Wei, a member of the Wind Elephant Sect. Li Wei was a coward who lived a life of regrets up until the day the entire Wind Elephant Sect was mu*dered. As Cassius relives Li Wei’s past, he makes different decisions to show Li Wei a different kind of future.By living out the ups and downs of Li Wei’s life, Cassius is introduced to the world of Covert Martial Arts, ties that run closer than blood, and supernatural forces. Crossing the line between the ordinary and supernatural, he realizes there’s no way back. New friends and enemies slowly integrate into his reality.Now, he must uncover the secrets of Covert Martial Arts and get stronger to survive.

If an ancient scholar searches through the mists of history, he or she will find such an existence:Pope of the night,Angel of the Creator,The hidden emperor of the empire,…He is also the perfect mentor;Wanmen’s guidance,The original source of pain...No one knows where he came from, only that he was born with knowledge and has been with him for years.Let us chant his honorable name together:Spirit of truth, pure man, master of dreams, supreme beyond all eternity