Naruto: Reborn with Kaguya Powers - Chapter 6: Training Regime.

A man is reborn into the world of Avatar: The Last Air Bender as a waterbender from Katara's tribe. Best of all, he was the same age as her, and he had a system with him to help.He knows the future and a system that lets him continuously get stronger by completing quests or long-term missions, as well as giving him the ability to copy abilities from others for himself. He will become invincible in the world of Avatar, even more so than the Avatar himself.

Syn, a dedicated guard in service to the ninth-in-line princess of a vast space station called “kingdom”, finds his life turned upside down when their ship is suddenly attacked by space pirates. Amid the chaos, Syn is shocked to discover that the leader of the pirates is someone from his past—a person he knows all too well.# Has femdom elements.

“Are you my knight?” The silver-haired youth looked at the blonde girl before him and asked, his cheeks flushed red. This was their first encounter when he was only ten years of age.

“Are you my bride?” He held her in his arms, embraced the girl who had accompanied him for ten years straight. He was sixteen years of age.

“Are you my king?” He knelt before the throne, smiling foolishly as he looked at the girl holding the sword victoriously. At this moment, he looked like the boy he was when they first met.

“I’m fine without having eyes for you. The entirety of Camelot is for your taking.” Smiling soft and gently, he gave his eyes to the girl who lost her eyes due to the curse of the red dragon. He doesn’t regret it, he thinks. He was twenty years of age.

“So… Arthur… Artoria Pendragon, are you willing… are you willing to spend the rest of your life with me?” His voice was soft and clear as he reached out to touch her hand.

This was their legend.

- Description from Novelupdates

Betrayed and left for dead, a soldier awakens in a world of knights and magic—but only one path is open to him.Hayden was once an elite soldier whose abilities were enhanced by the Ocularis Lens, a highly advanced mechanical eye technology.In this world that was filled with danger, Aura—a sacred energy that enhances the body and infuses weapons—is the mark of a true Knight, while magic is wielded by those born with the gift of sensing Mana.Hayden, however, is no mage. He doesn't have the ability to sense Mana, leaving him with only one option in order to survive: to become a Knight starting from a Knight's Academy!