Qinglian Chronicles - Chapter 81

The Sword Emperor’s challenges result in three of the Ten Venerables to be criticially injured. Three of the Seven Absolutes also die.“It wasn’t enough for you to come knocking at my door all alone; now you dare challenge me to a battle to the death? I did not think you to be so dull as to miscalculate others’ strength.””Neither the Ten Venerables nor the Yellow Lotus Temple’s Seven Absolutes of the orthodox sects had the ability to give me an answer. You are the only one left to ask.”Some may call the Sword Emperor old-fashioned, but he only seeks to be stronger as a martial artist.His endeavor eventually leads him to challenge the Heavenly Demon, the generation’s strongest man in murim. The challenge turns out to be the grand finale of his life.However, the Sword Emperor later wakes up as a member of the Cardenas family, the continent’s best swordsman family!

Some say reincarnation is a blessing, but for me, it's a dreadful curse. Cursed with endless reincarnation, I've been reborn as a villain 137 times. And all 137 times, I've been toyed with and killed by heroes who are far more cruel than the said villains... If I can't win no matter what I do, then I'll crush those so-called heroes at their very roots. - Quality Fan Translations, Made by Fans for the Fans - Villain Takes Over The Academy

Everyone in the City of Jing thinks that bestowment of marriage between Xian Junwang and the daughter of the Yi’an Marquis House is to insert a fresh flower into manure.

Xian Junwang was that fresh flower and the di daughter of Yi’an Marquis House was that manure that was not liked.

It is said that what is heard is false, seeing is believing. Who knows what the truth really is?

- 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.