Head Butler of the Fallen Villainess - Chapter 2: S-Rank Quest: Head Butler Position (1)

Arakawa Kouki is reincarnated to a Japan with a different history than the Japan he knows with the memories of his previous life still intact. Kouki was discouraged, “Aren’t reincarnation stories supposed to be at some fantasy world filled with swords, magic and elves?!”

She, a 21st century mercenary queen, had crossed over into a tragically betrayed body of a waste. Waste? She will show them what it means to be a waste! Betrayed? With the Ancient Manual in her hands, she will astonish all the despicable men and cheap women!

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.

Reborn into a failing noble family, Liu Xingchang awakens in a weakened teenage body, surrounded by humiliation and betrayal. Once the revered Sword God of the Northern Polar Heaven Domain, he now faces ridicule from his former lover, Yu Qiuer, who has abandoned him for a rival, and scorn from the very man daring to tread on his legacy.Though his power has diminished to a mere third-grade cultivation, Liu’s indomitable spirit drives him to reclaim his path to supremacy. When he fatally strikes his foe amidst the disbelieving crowd, even the noble Princess Qingyuan is drawn to this fallen “”coward’s”” defiant strength.Can Liu Xingchang resurrect his family’s honor, ascend to the Divine Realm, and turn the tables on those who scorned him?