Wolf of the Blood Moon: A Blood Magic - Chapter 67Book 6:

Xiao Ran transmigrated to a fantasy world. As a dungeon guard in the Celestial Dungeon, with a special floor called the Purgatory meant for powerful demons and martial arts experts, he faced a huge challenge from the start. The Eldest Princess acquired a forbidden martial arts technique and was banished to the Purgatory. However, no one was powerful enough to restrain her. All the dungeon guards were defeated. Xiao Ran stepped up and declared, “Your Highness, it’s better for you to behave yourself on my territory” and effortlessly subdued the Eldest Princess.

He progressed from imprisoning the Eldest Princess to delivering the Great Xia Kingdom from the evil clutches of various demons and evil martial arts experts.

…

Xiao Ran was the mastermind behind the scenes.

What’s worse than finding out you’re that Louis XIV when you’re a baby?

Of course there is, for example, it’s still a magic version.

- Description from novelbuddy

What the heck? She, a famous doctor from the 23rd century, turned into a village peasant girl of a different world!

Nagasawa crossed to Naruto Universe and was bound to Konohagakure.

If Konoha is severely damaged and destroyed, Nagasawa’s lifespan will be reduced.

He panicked at the thought of the upcoming Nine-Tailed Demon Fox’s attack , and the thought of Konoha getting destroyed left him in despair.

Fortunately, while bound to Konoha, he can obtain templates of powerful characters.

At the beginning, He got the Whitebeard template! Since it’s the Whitebeard from the Summit War of Marineford, he can use Tremor-Tremor Fruit’s ability and Haki.

Facing the Tailed Beast Ball, which terrorized Konoha Shinobi, Nagasawa leaped and shattered the Tailed Beast Ball with one punch!

- Description from Novelupdates