Infinite Comprehension by Taking In Disciples: Martial Uncle, Please Ascend! - Chapter 516 - 377: Ancestral Land of the God Race_2

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.

Shuu is a member of the literary club that can’t write. One day, he gets a mysterious message on his phone from a girl called Eina, and from that impulsive contact, they begin to exchange messages. They talk of things like their shared interest in novels and grow close. However, when they try and meet, they discover a shocking truth. Eina lives… not in the present, but five years in the past! How will their love develop, parted by five years of nights…!?

Bai Aoxue, the best mercenary in the 21st century, is accidentally sent back to the Chengxi Dynasty in Great Continent due to an explosion in her mission, and trapped in the first daughter of Prime Minister. After her rebirth, she is set up by her father to marry the 5th prince Jun Yeyan who wears a mask all day long.
In the face of bloodthirsty enemies, discord between brothers, collusion among courtiers and invasion of enemy state, can Bai and Jun resolve the crises? What will happen to their political marriage? How will the fierce battle for the throne end?
With many twists and turns, the book brings you to experience palace revolution, love and hatred thousands of years ago.

- Description from Novelupdates

Reincarnated and traveling to another world, Eiji Seiya initially thought the world was normal. That was what he thought before he met the heroine and protagonist of the franchise he had watched in his previous life.Not only that, after he awakened the Inner Voice System to grow strong by complaining about plot, heroine and protagonist in his heart to get many rewards.He is determined to increase his power so that he can save his home world, the world where he was reincarnated that was hit by the disaster “Honkai” and save beautiful girls like Kiana, Mai, Bronya, Rita and others who had tragic endings in the original works!“I will save them all!”However... Everything went smoothly... Eiji earned rewards every time he changed the plot in another franchise.It's just that... What's wrong with these heroines?Lala Satalin Deviluke who was supposed to be engaged to the protagonist instead became his fiancée.Sona Sitri suddenly called him to the student council office and said she wanted to make a deal with him.Rias Gremory who was supposed to ask the protagonist for help to solve her political marriage problem with Riser Phenex inexplicably came to him.The girls were disgusted at the protagonists of their respective franchises.Something was wrong here!Not only that, heroines like Kotegawa Yui, Sairenji Haruna, Akeno Himejima, Kuroka, Serafall Leviathan, Grayfia Lucifuge, Sakurajima Mai, Ai Hoshino, Kasumigaoka Utaha and others...They like him!All the super beautiful and sexy women that many men in the world covet surround him and leave their respective protagonists.Grayfia even betrayed her husband.Eiji who saw all this was dumbfounded.At first he was confused as to why these heroines were surrounding him, but gradually he realized and knew that it was all happening because ...His inner voice!The plot that has been changed by the MC:To Love Ru: 83%Highschool DxD: 82%Shinmai Maou no Testament: 92%Oregairu: 89%Saekano: 84%Oshi no Ko: 100%Rascal Does Not Dream Of Bunny Girl Senpai: 100%Mieruko-chan: 89%Trinity Seven: 38%This is the plot change process of the latest chapter and will change as the story progresses.By the way, the grammar at the beginning is bad and will improve as the chapter progresses. However, my writing style will not change much because this is an inner voice novel, which means that there will be many reactions from each character.Oh and in chapter hundreds there will be a group chat to prevent the loss of interaction between the heroines. It's a special chat group for the heroines in the MC's harem.