I Was a Sword When I Reincarnated - Chapter 444: Marquis’ Residence

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.

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

Eira Hax, the daughter of a once-wealthy heiress, has spent her entire life in the shadows.Twenty-two years ago, her mother, a kind-hearted but naive woman, was deceived by her husband, a ruthless businessman. He stole her entire fortune and framed her for a crime, sending her to prison, unaware that she was pregnant and secretly battling terminal cancer.Eira’s mother died alone behind bars, but not before giving birth to Eira, entrusting her with a burning desire for revenge.Now, two decades later, Eira returns with one goal: to destroy the man who ruined her mother’s life—her own father.To do so, she strategically marries his most powerful rival, Callian Reed, a man as dangerous as he is influential. Together, they plot to destroy her father’s empire, piece by piece.But as Eira is pulled deeper into a world of business, power and revenge, she’s forced to confront her own problems and decide just how far she’s willing to go to avenge her mother.“I’m not your enemy, darling…you should know that by now.”“Callian, everything you do is not written in our contract. Why are you breaking it?”“The more I learn about you, the more I hate everyone who hurt you. So please, Eira, let me get rid of them for you.”