Maou-sama no Machizukuri! ~Saikyou no Danjon wa Kindai Toshi~ - Volume 8 Chapter 16

Lin Li accidentally enters another world while playing with his smurf mage account just after he maxes out all kinds of crafting skills, bringing with him various top-grade materials. Although his character is practically powerless, what he gains in return is unprecedented magical talent! Can he survive by himself after being thrown into another world?

- Description from Novelupdates

Arakawa Kouki is reincarnated to a Japan with a different history than the Japan he knows with the memories of his previous life still intact. Kouki was discouraged, “Aren’t reincarnation stories supposed to be at some fantasy world filled with swords, magic and elves?!”

Fu Hongxue was a cripple, born with a lame leg and subject to epileptic seizures. He was also one of the most powerful, legendary figures of the martial arts world, with a dull black saber that was second to none. His fame made him a frequent target of challengers, but whenever his saber left its sheath, only corpses would remain in its wake. One day, however, Fu Hongxue rescued someone whom he should have killed…and in doing so, set of a chain of events and a conspiracy that would rock the world.