A few tutorials, including the one by simply-victoriax and Tamlo31 have been making rounds in the simming community lately teaching folks on how to create duplicates of worlds in The Sims 4. Although the tutorials are very handy, they require a lot of work, tools and effort to make this work.
Basically, with this tutorial you’re able to create an exact duplicate of the world that you’ve chosen, but edit it by your liking and have it inhabited by different Sims and lots that you decide to place down. With this you’re able to literally have as many Sims and lots as you possibly could image (or as much as your PC and The Sims 4’s engine can allow).
Now, Zerbu has come up with a unique mod that can easily duplicate a world of your liking:
With the mod installed, open the cheat console while in the world you want to copy (either in Build Mode or Live Mode), enter worlds.copy, type the name of the new world, click OK, then save*, return to the main menu and reload. That’s it, you now have a new world in your game!
The mod can easily be installed by extracting the zipped content to Electronic Arts > The Sims 4 > Mods folder.
NOTE: Considering that this is an experimental mod after all, make sure you backup your save game entirely before playing with this mod to ensure all your saves and progress don’t get corrupted!