DB: Legendary Super Saiyan Bloodline at the Start - Chapter 10: Beating Down Vegeta

The Third World War has been ended by the efforts of Kamijou Touma. With that, he vanished. With the Magic Side regrouping, the Sabbath for their followers has arrived.

In the headquarters of the Science Side, Academy City’s strongest Level 5 Esper Accelerator has washed his hands off the “Darkness.” Along with Last Order and Misaka Worst, his days pass by peacefully with no sign of GROUP.

Hamazura Shiage has formed a new ITEM with Kinuhata, Takitsubo and Mugino. Peace has come to the hands of the alumni who have “graduated” from Academy’s Dark Side at last… at least until a new evil “first year student” appears before them.

— This is a follow up to the popular Toaru Majutsu no Index light novel series, where Kamachi-Sensei has promised to deliver new premises and give a totally new flavor to the fights and plot developments

Awesome, I'm gonna catch a nap after lunch, and bam! Kidnapped.Of course, the damn floating screen in front of me tells me it's a once-in-a-lifetime 'job' opportunity as a streamer for all realities, living epic adventures, and whatnot.Well... except for the part where I couldn't refuse and kinda ended up in a damn forest with just the clothes on my back, I have no freakin' clue where I am, besides the fact that I'm no longer on my damn beloved planet, and apparently, there'll be a frickin' endless number of people watching me do everything?“I think I'm gonna have a freakin' aneurysm...”[...]It's my first time writing here, I've been wanting to write for a while now, so well, here we go. English is my third language, so there might be some mistakes or incorrect forms of writing, I apologize for that, if you notice any, please let me know, and I'll try to fix them.

Jiang Yu was a small mermaid who couldn’t sing. He had always felt inferior because of this. Not until he came to shore to find the father of his baby did he discovered that his talent turned out to be acting. Since then, he had trampled on the scum man, going on the acting road all the way, and progressing triumphantly.

Qin Shen: ??? You ran away after sleeping with me, and you still call me a scum man?

The not yet met Jiang Yu: Oh, it’s a small star who wants to hug my thighs.

The after contact Jiang Yu: Really fragrant.

Qin Shen found that things around him often disappeared, at first it was handkerchiefs, then ties, and then his shirt. And every time he lost something, there will be more pearls around him. One day, he caught all the things he had lost in that room, and he saw a little thief in his pajamas.

The little thief Jiang Yu is not happy, pointing at the jar of pearls, I am not a thief, I have money for you.

- 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.