Struggling as a Villain - Chapter 1 - 0- Death and rebirth

Gawain is dead and was transmigrated, but there was a slight problem during the process.
After floating for more than a hundred thousand years on a different continent, he felt that he might need a body to become a complete transmigrator, but he did not expect that…

A man who was once called the world’s strongest agent ended up becoming a teacher after his retirement, to train a new generation of agents. After many years of training his disciples, he was killed at the age of 60 by a secret organization’s ruse and was reincarnated in another world with his memories intact. Though he was surprised by the existence of magic and the strange species in that world, he quickly adapted to his condition as a newborn and took advantage of it. He acquired special magic and gained a massive amount of strength thanks to his rigorous discipline, in order to reach his goal: Resume his career as a teacher which he left halfway through in his previous life. This is the story of a man, who, based on the memories and the experiences of his previous life, became a teacher who travels through the world with his students.

Qiao Zhiya is a hybrid. Before he was born, his elf father wanted him to have a strong physique unique to dwarfs; his dwarf mother wanted him to have a tall body unique to elves. And then he was born, his features delicate and beautiful, his body weak and thin… his strength at the peak of the dwarfs!

Then he crossed. With his beloved little hammer, we walk along females-who-is-as-tall-as-he-is and male-who-is-a-head-taller-than-him-on-average future… blue, thin mushroom wants to go home.

Chu Rong: picked up a small dwarf who always wants to run away. Its cute, wanna drag home.

Qiao Zhiya: ??? Mama, there’s a pervert!

- Description from Novelupdates

He became a teacher at the best magic academy in the empire.
….For being mistaken for someone else.