You, CEO's Secret Wife - Chapter 644

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 series of short stories in the world of Toaru Majutsu no Index organized into chapters featuring Kanzaki Kaori as the protagonist, going around the world and space doing missions for the Church of Necessary Evil, however, there is more than meets the eye as each incident is connected.

One chapter was bundled with each limited edition release of the Toaru Kagaku no Railgun anime DVD and BDs, with all of them together being equivalent to a single normal Toaru Majutsu no Index volume

A god of a different world had abruptly appeared in my classroom and semi-forcibly summoned the entire class to his world.ーーーーexcept for me, Kamiya Yato.

Ten years ago, Magnolia was blamed for her sister’s death and cast out of her pack. Her Alpha father’s final words “Why did she die, but not you?” drove her into exile. She lived among humans, hiding her identity, her wolf, and her pain.Now, at twenty-eight, Magnolia learns her mate is none other than Rhett Callahan , the powerful Alpha of the strongest pack and heir to a billion-dollar empire. But instead of love, he offers her a contract: marry him for one year so he can fulfill the requirements of his inheritance.Magnolia accepts to save her parents’ home but finds herself in a loveless arrangement, mocked by the pack and haunted by the past. Then Camille returns with another woman, the one he truly loves… and it’s Magnolia ’s sister, long thought dead.As secrets explode and bonds unravel, Magnolia must decide if she can forgive the mate who rejected her or burn the past down with him in it.