Media Format

Example SKU import:

External ID,Name,Default Category,Url,MSRP,Description,displayProductOptions,defaultSku.skuMedia---primary,media
MY-EXTERNAL-ID-001,My SKU,2002,/mySku,9.7,My SKU Description,FALSE,/cmsstatic/MY_SKU_1000x1000.jpg,alt1:/cmsstatic/MY_SKU_2_1000x1000.jpg|alt2:/cmsstatic/MY_SKU_3_1000x1000.jpg

Notice there's a difference when handling primary media vs other media references. You will need to explicitly define it in its own column due to the way that @AdminPresentationMapProperty entries are defined on the entity.
You will need to define it based on how it looks in the admin pipeline. For the primary media this is defaultSku.skuMedia---primary

This will create the following items with the category.getCategoryMedia(), or product.getSku().getSkuMedia():

Note that this just hooks up the association of a URL to a media item. Actually uploading the static assets themselves is handled differently, see [[Asset Import]].