The Debt To The Chosen One

The legend Beasts and legendaires see ash suffers so much. Due to him him constanly saving the world . They decide to take him away/ make him immortal , and they then gave him his own world. Where everything he wants is real. However due to this, the world gets worse to a point. Where the legends are planing to get rid of most humans and start anew. Can Ash's friends stop whats going to happen?!
This will have ships, Mew two x ash will be in it as well as enti x ash. Don't judge me for the last one please (-_-)^