Why aren't there any system templates in my child theme folder in Design Tools?

All templates in a child theme are inherited from the parent theme and do not need to be included in the child theme folder

The child theme automatically inherits the templates from the parent theme, so even though you don't see template files in the child theme, there are still 2 versions: the marketplace version (most likely POWER branded) and your child theme (with your brand).

The only templates or modules that need to be cloned to the child theme are those where you are making structural changes to the module or modifying the template content. Any other changes can be made in the child.css or child.js files.