Step 1 - Be sure that your site has set these options: (From Dashboard > Appearance > NasaTheme Options > Variation Swatches)
Step 2 - Go to Products > Attributes then create the variation is the brand and change the swatch type into Custom Image. Then, you must provide an image for each Variation by clicking the Edit each Variation and upload its image.
Step 3 - Next, please add and custom attributes on the Single Product: Navigate to Products → All Products in the WordPress admin and select a product from the list that you need custom this feature:
Step 4 - Please enable this feature to show brands on the single product page: From Dashboard > Appearance > NasaTheme Options > Product Brands: