Becoming the Empress: Golden Finger Set Under My Bed - Chapter 4: Second Prince’s Visit

Going against the heavens, Tuoba Ye reincarnated. Body concealing Divine Root, hands holding Divine Talisman, possessing previous life’s experiences, from childhood, began cultivating the most difficult body refining method: Mythical Nine Transformations.

- 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.

A teenager named Evan Mason was reincarnated into the magical world of Harry Potter and goes to school at Hogwarts!

With only his knowledge of the future and great talent for magic, he takes the path towards the top of the magic world, only to realize that ever step he took, changed everything!

After traveling through time and space and becoming the younger brother of Uchiha Fugaku, Uchiha Yuto felt very panicked! He was preparing to practice hard to become the God of the Ninja World and suppress everyone, but after graduating from the Ninja Academy, he suddenly discovered that he had another path to take!“Itachi, don’t be a ninja; be a prodigal son! Uncle will give you money. The more you spend, the more popular you will be.”Being a ninja can't save the Uchiha! — Uchiha YutoThe more money Uchiha Yuto makes, the stronger his abilities will become!