MTL - Naruto: I Became Naruto’s Blackened Personality - Chapter 9

Zhong Li, an orphan in the 21st century, was wondering how to collect the fees for his college study on the street, when he was suddenly hit by a car, which threw him into a river. An orphan’s disappearance would not bring too much attention to the world, but this accident gave Zhong Li another chance of living a glorious life in an immortal world. When he woke up, he found himself lying in a magnificent yet strange palace built of all gold, but had no door. An immortal claimed to be his savior and wanted to train Zhong Li with all of his cultivation methods, only because he was too lonely and wanted a disciple to keep him company. When Zhong Li finished his study, the master would tell him how to go out of the palace. Zhong Li never thought that the path to immortality would bring him to the fate of becoming a dragon.

- Description from Novelupdates

Known as the youngest academician-level senior engineer, Zhao Guoyang was reborn in the 1990s. In this era of economic globalization, with his extraordinary wisdom and extraordinary insights, he created one miracle after another and became a name that shocked the world!

Wisdom is condensed every bit, brilliance is created by sweat, and witness the rise of a great power!

- Description from novelbuddy

The story is about a a hitman, Who dies because of his own recklessness and transmigrates into a game he used to play after his retirement as a hitman.I'm not gonna spoil any further, but i might answer few of your questions.Is MC overpowered?Nope, he'll become strong over time and all battle he'll fight will be because of his effort and techniques.Is there magic and adventure?Yes! It have both magic like normal isekai with adventure and fighting with monsters and many other things. There are other important things like “Essence Stone” But let's talk about it in the chapters.There will be harem?Not really, He will be in contact with many beautiful female and males but one waifu but i haven't decided yet.All i can say is, give it a try, I'll try my best to make it worth your time.