WT Category

The plugin is needed more for Joomla developers, since Joomla itself does not allow one entity to be in several categories at once and the plugin may be useless to an inexperienced user. 
Minimum Joomla version is 4.2.0.

Plugin Parameters

• Is Joomla core component? - If the selected component is a Joomla core component, a drop-down list of components will be displayed. If it is a third-party component, then specify its name like  com_component in the next field.
• Component name (com_component) - Specify the name of the com_component or com_component.entity component to select a category.
• Multiple - Allow multiple categories to be selected in the field or not.
• Published - Show only published categories in the drop-down list of categories or enable the display of unpublished ones. Trashed and archived categories are not displayed.
• Language - Show categories only for the selected content language.

GitHub - https://github.com/WebTolk/WT-Category-Joomla-custom-field-plugin-for-categories-selection