Forge version - 1.20.1 - 47.4.0
Heartstone version - 1.20-1.3.0
Visual Workbench version - v8.0.0 - 1.20.1 (https://www.curseforge.com/minecraft/mc-mods/visual-workbench/files/4612697)

If this mod Visual Workbench is installed, then your amethyst hearts cannot be connected, that is, if I put two hearts in the workbench, they will not be connected and a unique ID will not appear, and they will not work between players.

thats not how heartstone works. You get 2 connected hearts every time you craft one. you should get 2 duplicate items per recipe

Then it's extremely likely they are breaking stuff as I'm not even using a special recipe. Report there

thats not how heartstone works. You get 2 connected hearts every time you craft one. you should get 2 duplicate items per recipe

This feature also does not work if the Visual Workbench is installed.