In PLP its show option sort by Brand option while click on that items of that brand will show.

Steps:
Step 1: create a custom Item name it as CUSTOM BRANDS and type as List/Record and add list of brands

Step 2: Add CUSTOM BRANDS to website Search Index > Sort Fields

Step 3: Add Brands to respective items which is showing in custom sub-tab.
Step 4: Make cache Invalidation Request.