With this datapack/mod installed, you and your friends all share one Inventory! This applies to your Hotbar, Inventory, offhand and your armor slots.
This project is both available as a mod and a datapack. If you install the mod you'll still need to enable the datapack from the world creation screen.
INSTALLING THIS AFTERWARDS WILL DELETE THE INVENTORY OF EVERY PLAYER EXCEPT ONE. THIS IS IRREVERSIBLE
The Commands used where shown in this video by BlockerLocker. I just made them into a datapack!
