It's pretty much explained everything in the title so...

「ARKNIGHTS 」⤫「Jujutsu Kaisen 」 What if Sukuna transmigrated into Arknights? The King of Curses walks through the Pathway of Souls and finds himself wandering into the world of Arknights. "Should there be a next time... perhaps it would be nice to walk a different path." Arknights - Hypergryph Jujutsu Kaisen - Gege Akutami, Shueisha & VIZ Media

Yuji Itadori was born in a Japan filled with heroes, villains, and rankings impossible to keep track of. And he... doesn't have a flashy Quirk, no sparks, no fire, none of that. The only thing he comes with by default is a ridiculously strong body. His entire adolescence was normal, but it's hard not to stand out when you open a door and bend it by accident, or when you break the records in P.E. without even trying.

During the devastating final battle in Shinjuku, Yuji Itadori gives his all to stop Sukuna, even if it means sacrificing his own life. Just as the final blow is struck, an unknown energy rips the fabric of reality and pulls Yuji away at the last moment. When Yuji awakens, he finds himself in a completely different world: a medieval kingdom called Lugnica, where magic is real and monsters roam the forests. Confused and weakened, he is helped by a young blue-haired woman named Rem.

[ON HAITUS] While V1 is traveling through the nine layers of hell, a mysterious force wrecks his body and leaves him fending for himself in the world of Zenless Zone Zero. Follow V1 in his exploration of the crazy noisy bizarre city of New Eridu.

The King of Curses was expelled from the body of the Zenin's Blessing by the Black Spark's Chosen Sorcerer, but not without a cost: His own life. Or at least, it seemed so. In the aftermath of Sukuna's defeat, Megumi Fushiguro finds himself in another world, a World without Curses but one filled with darkness, under the shattered light of a broken moon. NOTE: Alternate Universe, Pre-Canon

This is a what If story. what if Modulo Yuji went to the Re:Zero World. Enjoy.

(I do not own JJK or MHA) *deja vu? After Yuji Itadori unleashed his final black flash against The Strongest in History in the destroyed city of Shinjuku, he thinks it is over, but after he passes out from a mysterious force. He lands in an alleyway in an alternate version of Japan where "Quirks" reign and Heros and Villains exist. What will Itadori do in this society?

In a world where humanity fights for survival against the Shuuki monsters lurking within the dangerous dimension known as Mato-only women possess the power to stand on the front lines. Men? They exist to serve. To assist. Or to be used. ​Denji knows this better than anyone. Drowning in debt and forced to work under the Yakuza, he survives as a disposable Shuuki hunter, risking his life daily for scraps of money... and the faint hope of a better life. His only comfort is Pochita, a strange Shuuki who, for some reason, chose to stay by his side. ​But everything changes after a deadly incident inside Mato. ​Betrayed and left for dead, Denji fuses with his loyal companion, becoming something impossible-a hybrid wielding a power no man should possess. Saved from the brink of extinction and drafted into the elite Demon Defense Force, the boy who was once ignored suddenly becomes the center of attention. ​Now, integrated into a world of powerful commanders and elite warriors, Denji finally has a chance to chase the simple dreams he was always denied. But carrying a legendary power means all eyes are on him. As dangerous forces-and ancient entities-begin to take interest in the chainsaw devil inside his chest, Denji will have to fight not just for humanity's survival, but to protect the first real home he has ever known.

When Toji Fushiguro is mysteriously resurrected in a world of magic and monsters, he's granted a third chance at life. Thrown into an unfamiliar realm, he crosses paths with a determined girl on a quest to recover a stolen insignia. Bound by a strange contract to protect her, Toji must navigate this perilous world while confronting his own uncertain fate. With danger lurking and each decision crucial, can Toji master his new reality, or will his third chance unravel in unexpected ways?