In Naruto: Reborn with a Chat Group - Chapter 95 - : Kunai Aimed At The Ass

Before his death, he was the only sword cultivator in the whole world, who dedicated his entire life to the path of sword immortality.

When he opened his eyes again, the world had completely changed. He began to cultivate the path of sword immortality again, slaying the heavenly way, shattering the universe with his will, and achieving the realm of sword immortality!

- Description from Novelupdates

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

Betrayed by his former gang and thrown into the Rendhold Underprison, Dantes has spent the last five years scraping by. A whoreson of orcish, human, and elvish blood, he's lived on the periphery of the periphery, lying, cheating, and stealing to survive. After a run of bad luck, he's made a powerful enemy. Luckily, he's also gotten all the tools he needs to turn things around.A slow burn progression fantasy focused on rising through the criminal underworld of a city-state using newfound powers and quick wits.MC's powers will develop slowly, but he will use them in creative ways to get ahead, and in the meantime he's not above just braining someone with a club.Anti-hero/villainous MC with a code.

One day, Yoichi who grew up while not knowing his parents has received the news of his father’s death. His father left behind a testament——which said he is to pick only one out of five ‘little sister candidates’?!