https://unicorn.comic-ryu.jp/series/isekashinsengumi/ Although they died at different times, the elite members of the Shinsengumi are reincarnated into the same other world. Reunited, they re-form the “Shinsengumi” to protect the capital from the invasion of the demon race!

Five handsome men from an otome game are reincarnated into the life of Tokiko, who loves otome games! (Source: Kodansha, translated)

Society is suffering from an unprecedented rate of unmarried people, combined with an aging society and a declining birthrate. The government has begun to take serious measures to combat this problem. Satoshi is selected as an operator for the "Perfect Match Machine," a machine created by a mad scientist to find the one-in-100-billion perfect couple who are destined to be together. A futuristic dating service comedy! (Source: Shonengahosha, translated)

A story about a pair of clones living in a post-apocalyptic world, who encounter another person for the first time. (Source: Rookie Jump, translated)

Seto is a serious kid who leads a quiet High-school life, until he starts to get teased by resident Gal Anjo. Note: While the pixiv album for the Preserialization has 25 posts, there are only 23 Preserialization chapters because the 23rd post is Serialization Chapter 2 and the 24th post is Serialization Chapter 14.

Gouseiken Dai Sword" is a manga work by Yuichi Hasegawa. It is an adventure fantasy manga in which the main character, Ota Momochi, and 550 other junior high school students are transported from their school to a different world of swords and magic.