MultiWorld is a skript allows you to redo all or almost all the functionality of the MultiWorld and Multiverse-Core plugin.
Spigot: https://www.spigotmc.org/resources/multiworld-skript-1-16-5-1-18-2.92889/
Plugin Requirements:
Skript: https://github.com/SkriptLang/Skript/releases
SkBee: https://github.com/ShaneBeee/SkBee/releases
Skript-YAML: https://www.spigotmc.org/resources/skript-yaml.49829/