As Sukuna in Invincible - Chapter 59: What Remains

Garou woke up in the world of Naruto, reborn as an ordinary civilian of the Hidden Leaf Village.To his shock, he discovered he suffered from the same limitation as Rock Lee: completely talentless in both ninjutsu and genjutsu. Worse yet, he belonged to the same generation as Naruto and the other members of the Konoha 12.But Garou wasn’t the type to quit. He knew that pure grind beats natural talent.Might Guy had already proven that much.However, unlike Guy, Garou had seen the end. He had watched the anime.He understood that taijutsu, as powerful as it was, always burned out like a firework, brilliant but brief.And this time, he had no intention of going out like that.Determined to break past the limits, Garou began creating his own techniques, pushing the boundaries of what a “mere” civilian could achieve.And the mysterious light orb in his mind granted him powers based on the influence his techniques had on others and the world itself.The world of Naruto would never be the same again.The grind doesn’t stop until the world bows before his fists.

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.

In the future timeline, Humankind had developed things that brought a revolution to the world. But their best invention was fully immersive VR games that became more and more advanced as time passed. They could create new worlds— in virtual reality, that was more beautiful and profound than the real world they lived in.

Although Leng Ruoxue is born mentally challenged, she is the most beloved granddaughter of the number one general in the Eastern Lake Nation. She is despised by her fiancé and schemed against by her love rival. However, she is reborn as a powerful soul. This is a fantasy world, and also a world where the strong are respected. Cultivation, alchemy, weapon refinement, beast taming—the once foolish young miss has transformed into a stunning genius. Pill refinement and weapon refinement are all child's play. Heaven Grade medicinal pill? Even my pets won't turn an eye to it. Heavenly Treasure? I have the space to grow my own. Sacred artifact? Sorry, that's too low a level. I only know how to refine divine artifacts. Beast taming? My beasts deliver themselves to my doorstep.