This data pack links the health between all the players in the game, no matter where they are. Whenever one person takes damage, everyone does. And the same is true for natural regeneration.

Furthermore, this data pack is compatible with players of different health pools. This means it works for mods, such as origins.

Installation

Simply download the data pack and put it into the "datapacks" folder inside the folder of the minecraft world, or just add it in when creating the world. By default, all players who enter the world will share their health with each other. However, if you head into the folder, and navigate over to data/ch/function/main.mcfunction, you can disable that feature by commenting out that line.

Furthermore, you can use /function ch:admin/enter on a specific player or players with the /execute command in order to add them into the health sharing, and likewise use /function ch:admin/leave to disable their health sharing.