Is there a way to create a sub-filter inside the size filter? I'd like to get my sizing more organized and to create essentially a sub-filter or a size grouping labeled Alpha for size (XS, M, L, etc) and another group inside the size filter for Numeric (0, 1, 2, 3, 4, etc). We're using the Prestige theme.
We'd like it to function similarly to the https://www.freepeople.com/ filtering.
You can ask the support team at Ultimate Filter & Search app to customize the Size filter to meet your requirements. It's out-of-the-box solution that can filter by variant options and help you merge similar values into a common one. https://docs.sobooster.com/search/product-filtering-guide/add-filter-options
It allows you to test the app on a duplicated theme without affecting other themes in your store.