The God of Sky & Earth - Chapter 1: The Jinx Is Back

Before the rebirth, Gu Qingyao wanted to marry him but did not dare to marry. After the rebirth, Gu Qingyao, with the space materials in hand, all day planning to marry him with a huge dowry.

Ethan Carter was a failed fantasy author who died overworked and bitter. When he wakes up in the world of his own unfinished novel, he finds himself reborn as Darius Wycliffe, a weak and arrogant noble fated to be killed by the protagonist, Lucien Ashford, the Archmage’s Disciple.But Ethan refuses to die so easily. Armed with his knowledge of the world’s secrets and a unique ability to rewrite spells, he dives into the forbidden magic he once created but never fully explored. As he grows stronger, he uncovers terrifying truths about the world he thought he knew.To survive, Ethan must defy destiny, master the deadliest of magics, and challenge the very hero he once wrote to be unbeatable. But what happens when the lines between hero and villain start to blur?

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.

Once upon a time, an Alchemist Grandmaster from the World of Immortals accidentally took possession of a playboy, who hailed from a rich and powerful family, and became a student in the middle of his midterms.

By the means of a miraculous immortal technique, he blended in and mingled amongst the femme fatales’ group to dominate the city! The nature of this novel’s origin is shamelessness to the core; having no sense of shame is just a basic foundation, but if the most shameless isn’t set yet, then become it!

- Description from Novelupdates