There is another problem. When configuring Hotbar, the icon disappear
Viewing post in [SOLVED] Found a problem
First issue is fixed and will be ready in next update of Hotbar plugin. For the second issue, it's likely due to your RPG Maker MZ isn't up to date. The latest version is 1.9.0
Update: Please update Hotbar Creator to ver 1.2.3 and it'll be fixed. The second issue you need to update your RPG Maker MZ.
https://sanghendrix.itch.io/hotbar-creator-rpg-maker-mv-mz-plugin/devlog/898297/...