Use of the Astratic Child Theme (instead of the parent Astratic Theme) is recommended when you plan to modify or overwrite the source code of the theme.
If you are making extensive customizations – beyond styles and a few theme files – creating a parent theme might be a better option than a child theme. Creating a parent theme allows you to avoid issues with deprecated code in the future. This needs to be decided on a case-by-case basis.Source: developer.wordpress.org
Sometimes there may be a situation where you started using the parent theme and next, you want to make modifications inside the source code – therefore switch to the child theme.
By default, the customizer or Full Site Editing settings not be moved to another theme after that.
Fortunately, there is a solution to this – you can use one of the plugins:
- FSE Design Import/Export – is for moving settings of the Full Site Editing
- Customizer Export/Import – is for moving settings from the Customizer
With the above plugins, you can switch from parent to child theme (or conversely) without having to rewrite the settings manually.