Naruto: I Can Take People Through the Ninja World in the Future - Chapter 318: Space-Time Loophole

Xia Yan passed through to the world of Bleach and became an eleven-year-old boy. He was rescued by Renji and Rukia in the Seireitei, and he was studying at Shin’ō Academy, and he was a student of the same class.
He is a top student of the Shin’ō Academy, and he is vying for strength by various teams. In the end, he has entered the first team of secret mobile maneuvers.
He will use punishment to kill every person who tries to threaten the martyrdom and protect his loved one.

- Description from Novelupdates

When Kim Seojin opened his eyes, he found himself three hundred years in the future.In the last three hundred years, humanity went through a lot of changes. Science had developed, cities became more modern, and space travel became a reality. But all of that came at a cost.The world had become a plaything of gods. Every year, humans were selected to represent their race in a devilish game, all for the entertainment of the gods.Kim Seojin was one of the thousand people selected in a timeline where he didn't belong.There was one more person. A Regressor burdened with the memories of countless failed timelines and the knowledge of the destruction to come, was also a part of the game…

Previously one of the ten greatest Martial Emperor, Gu Feiyang somehow died near the mountains of Heaven Wave.

Fifteen years later, Gu Feiyang crossed through the cycle of rebirth. He was back! But this time, he was in the body of Li Yunxiao. Since then, Li Yunxiao started a treacherous journey. The world is in turmoil once more!

- Description from Novelupdates

As a reward for preventing the assassination of the current king, Rou Coral is rewarded with becoming and escort of the Royal Princess Reaina who the boy adores so much. Thus begins his new life of servitude under his beloved high-headed Princess full of happenings and happy little accidents. Surrounded with Busty Head Maid, young Loli Princess and a Childhood Friend Maid, for the boy knight today is yet another day of struggle in this womanly paradise!!