This plugin provide to set perms to change world

USAGE
First, add your world's name to config (plugin also can do it automatically but if it don't, add manually).

Second, set value of world as true (if you set as false, all players can spawn that world because plugin will not check that world).

Then, reload plugin (/reloadworldperms)

Finally, give permission "worldperms.world.%WORLDNAME%" to player who you want to enter that world