The Overlord of Blood and Iron (WN) - Chapter 4

A world filled with heroes with superpowers. A world attacked by calamity fiends. A modern world filled with wonders and dangers.

Shi Xiaobai, a child from normal Earth, walked into such a world, proclaiming to be its king. But at the first signs of danger, he is forced to make a choice, one which he cannot refuse for time would repeat, making him face the choice again.

He is not humble nor is he modest, but neither is he delusional. Yet, the Absolute Choice seems to make fun of him. Will the joke be on him or will he laugh at his opponents? There will be many watching his escapades, and there will be some joining him in his adventures.

To see through the world and to grasp its truth, that is the destiny of the King.

- Description from novelupdates

Leiyin accidentally crossed into the One Piece World, and accidentally obtained the Naruto System.

Trying to earn a living everyday kept Hyun-Soo busy. However, one day when he was doing a side job of threading beads, he realized something.

-Ding!

All Things of this World, Turn to Ashes, Flowing Blade-like Flame!

Crossing over to the world of pirates(the one piece world) , in the era of pirates, the Roja from eleven years ago obtained a Sword Soul system that lets him strengthen infinitely and extract various kinds of skills.

Flowing Blade-like Flame (Ryūjin Jakka) , Mirror Flower, Water Moon (Kyoka Suigetsu), Moon Fang Heaven-Piercer (Getsuga Tensho), Thousand Cherry Blossoms (Senbonzakura)……

“If this sword descend, you may be roasted to death.” Roja looked at Akainu in front of him and seriously said.

- Description from novelupdates