last battle on remnant

What happen if there are four traverler come from different world and diffrent time.

A former huntsmen in tranining, who work alone in a world, where people only care for fame,money.

A delivery guy, who want just live a normal life in world, where only female have power but a parkage found him.

A former preverts human, who just wanting to achieve his dream to become a harem king but now he wonder about his dream.

A star went through many world with his sibling but later they got capture and went into slumber before he wake up to find his sibling.

What happen if they got into one world only, where the people they don't know about them not exsit from their world.