I love the app! This is my third biggest gripe with it. When adding an item to Square under Items - not to the shopping cart - and you try to add a photo, you can't add a photo directly to a Variation. Because Square for Retail is designed to work best with photos, and because the variation photos actually show up in the checkout experience, it would make sense that you'd want to provide a way to easily add photos on all the variations. Alas.
The main image is the only image you can edit.
You can't add images to Variations.
Even if you open up the variation.
Square Community