The Variant Tagger was primarily developed to enable store owners to filter by variants - such as size and color. If you have worked with Shopify you may know there is an issue where if you try to filter by variants, it still displays out of stock items in collections.
This is because if you create a collection rule such as 'Variant Title equals Large and Inventory > 0' it will still add the product if sold out in that size. The reason is that the inventory count is calculated on the product, not the variant.
The Filter Menu integration can save a lot of time and make sure you don't need to delete variants when they are out of stock (the old method).
How it works
When creating a new rule you have the option of adding a filter group. This will then:
Tag all products with the available variant options.
Automatically create a collection for each variant tag if one does not exist.
Add the collection to the filter menu (sorted alphabetically on the tag).
Save the filter menu and update your site.
Setting it up
Firstly create a new group in the Filter Menu. By clicking on the 'New Filter Group' button.
Give the group a title, such as 'Size' and select 'Variant' as the type of filters you want to set up. Then click the 'Create Filter Group' button.
Now you can create a new variant tag rule for sizes.
Make sure that the variant title you provide matches the variant title's on your products exactly.
Click the 'Add Variant Filters' button to finish up. When you save the app will update the tags, create any required collections, and update the Filter Menu all in one go.
If you have any additional questions, please contact support through the live chat in the app, or at firstname.lastname@example.org