The Magic Academy's Physicist - Chapter 9: Countdown

Kamishiro Homura is a hero who once by himself exterminated the another world invader that destroyed the military all over the world. However his extreme strength made the influential people ostracized and exiled him from the society with false accusation of [Traitor] attached to him. A few years after that, for an unspecified reason Homura entered the magician academy and he looked after the girls that were ridiculed as the [burden platoon]…!? This is the raise of the curtain of a fantasy tale of the unrivaled and invincible young man where not a single ally or enemy can keep up with him, the young man who sooner or later will be extolled as the messiah by the whole human race!

Two years ago, the famous teenage e-sports genius, Daylight, accused an opponent of cheating in a competitive game and eventually disappeared from e-sports.

Two years later, the small streamer (ShadowBlade) dominates in an Overwatch match and runs into the super famous streamer, (KangMing).

Kang Ming: Can you shoot me again?!

– YOU WERE ELIMINATED BY SHADOWBLADE –

Kang Ming: Oh.

Then ShadowBlade finally realized: if I want to die, I must do it myself.

- Description from Novelupdates

Gojo Satoru always knew he could travel back in time whenever his life was in danger. After surviving betrayal, the battle at the Prison Realm, and his fight with Sukuna, he realized he needed a fresh start. When he opened his eyes, he was sixteen again—his first day at Jujutsu High. Nothing had happened yet. This was his chance to change everything.But something was wrong. Geto Suguru was missing.Gojo searched all of Tokyo but found no trace of him. Then, a year later, during a mission near Shinjuku Station, he spotted a familiar face—a boy with a bun and strange bangs.Gojo’s heart raced.Geto Suguru: “Who are you?”

You thought being reincarnated as an extra-side character was bad? Imagine being thrown into the body of a villain who is disowned by his own family and discarded by the author.