MTL - Master of Ninja World - Chapter 145 Youyou years [Various requirements]

A normal person, Xin Yun, received a second chance by transmigrating to an unknown world. But because he chose to indulge in women, he lost his chance to become the most powerful.

When he gets caught by the force a struggle between the nine most powerful experts, something unbelievable happened, or it could be said that a miracle occurred. Xin Yun was reborn and sent back to the place he had transmigrated over to.

Having been reborn, Xin Yun decided he wanted to become the strongest being together with the three top experts from his previous life: the most beautiful dragon- Sparkling Butterfly, Yi Luo Xiang, the cruel dragon- Evil Empress, Yan Qing Ying, and the most dazzling dragon- Peac*ck King, Ming Xuan!

Furthermore, he wanted to pursue love with the most beloved person from his previous life- Yi Luo Xiang! Xin Yun, making use of his good fortune, used his memories from his previous life to prioritized becoming friends with Yi Luo Xiang, Yan Qing Ying and Ming Xuan. He even received a godly artifact from his previous life- the Heaven Splitting Axe!

- Description from Novelupdates

At nineteen, Dexter was already one of the world’s most celebrated authors. His books topped charts. Critics praised his genius. Fans devoured every word. But behind the acclaim was a lonely boy—raised without parents, love, or real friends—just stories.He published his first novel at fourteen. By seventeen, he was a literary star. But the higher he rose, the hollower it felt.Then came the writer’s block. The headaches. The blackout. And the transmigration.Dexter awoke in the body of Daylan, a disgraced young man in a crumbling, medieval world laced with steampunk tech, divine law, and political unrest. Daylan had already failed two of the three sacred Trials—rites that determine one’s magical potential. He was drowning in debt, entangled in plots to overthrow a corrupt Divine Church, and branded a lost cause.With no way back, Dexter took the final Trial—the most brutal of them all—and began a path that would earn him the whispered title: Soldier, Poet, King.But as his powers grew, one question haunted him: Did he truly die? And if so, who—or what—chose to bring him back?

A wonder falling down from heaven! A boy possessed by strange blood! Gods tremble! Demons flee! A boy from the land of Dong Zhou. A pink skull as his sworn friend until death. A story of a determined warrior struggling for power. A legend that shakes the galaxy and disturbs the worlds of god, demon and man.

- Description from Novelupdates

Zavier met Cosmic Consciousness after his death. He was satisfied with every system that Cosmic Consciousness exhibited, so he wanted all of them. Surprisingly, the Cosmic Consciousness obliged him.

Zavier was reborn in an isekai full of magic and alchemy. Now, he had many routes to upgrade. Interestingly, to coordinate these systems, Cosmic Consciousness gave him the gift of being able to duplicate himself. He could clone a finite number of himself to manipulate these systems.

Magus, Alchemist, Mesmer, Tamer, Hunter, Vampire, Werewolf, Dragonknight, Necromancer.....

-----

By the way, it wouldn't appear NTR or some bullshit harem of courtships. MC of course will have harem but not for cliches.