No Cheat in Bleach ? Watch me help Aizen then. - Chapter 5: The Noble Hunting Festival

A Federation Colonel with abnormal thoughts was locked in a dark room and met a little looney.

“Your whole body emits a scent that I dread (covet) and fear (desire).”

A frigid Colonel X little looney roommate: A sweet story of interstellar travel

- Description from Novelupdates

Joshua woke up in the middle of a battlefield one day only to discover that he has been transmigrated into a popular MMORPG, Continental War. Discovering that he has not only been displaced in space but also in time, Joshua realizes he has knowledge of the events unfolding around the world as he had played through them as game events. Read on to discover how Joshua forges his path towards becoming a legendary warrior!

Waking up, Kim Hajin finds himself in a familiar world but an unfamiliar body.

Su Yao passed through and traveled to the Marvel world to become a mutant. He was still in the experimental base. He expressed a little panic…

Fortunately, at the critical moment, the mutant ability ‘imitation’ was awakened to imitate the opponent’s ability!
…
Imitation object→Orochi (title: Sun God, Will of the Earth)
Imitation object→Wanda (title: Scarlet Witch, owner of chaos magic)
Imitation object → Sun God…
…
Professor X: “We must find him as soon as possible and guide him to control his power to avoid causing irreparable disasters!”
Magneto: “You are my child???”
Thor: “Brother?”
Loki: “?”

- Description from novelbuddy