Nightfall - Chapter 271: Liansheng 32 (II)

After dying, you wake up and realize you've been reincarnated as a background character who is judged as human trash.The decision to change your destiny comes instantly.Discovering that your identity isn't as simple as you thought, you feel favored by the heavens when you manage to become a powerful character.Katase: You won't fool me. I'll expose you for the pervert you are.Murayama: ...Thank you for saving us.Issei: Motohama, what happened to you? How are you so powerful?Rias: If you join my peerage, I wouldn't mind being yours.Sona: You beat me in the game. That means you're now my fiancé.Yasaka: Honey, Kuno wants a little brother.Kaori Houjou: Shinji-kun, let's go on an adventure.Kaede Kazama: Shinji-kun, thank you for saving me from that ball.Rie Sawada: Shinji-kun, I'll wait for you. You'll be my future husband, fufufufu...Changing known history and taking it in a direction not even his eyes could perceive, he didn't stop no matter what. Not even the other world was safe from his clutches.Lexia Von Arselia: My hero, and my future husband...Shinji advances without stopping.“I, Shinji Motohama, swear here and now that I will reach the top of both worlds.”

In Ten Heavens Domain, full of respected powerhouses, juvenile Ling Tian accidentally obtained a mysterious iron sword. He refined the Supreme Martial Dao, studied the Divine Spirit Array Laws, fought Ten Thousand proud and arrogant Heavenly Clans, and was undefeated! Seven Feet Sword Tip sweeps away the world, within the Ten Heavens, I am the Supreme God Monarch!

- 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.

Killed by a Sage Emperor and reborn as his 13 year old self, Nie Li was given a second chance at life. A second chance to change everything and save his loved ones and his beloved city. He shall once again battle with the Sage Emperor to avenge his death and those of his beloved . With the vast knowledge of hundred years of life he accumulated in his previous life, wielding the strongest demon spirits, he shall reach the pinnacle of Martial Arts.