Mac here from Shopify.
Thank you for taking the time to install and try out an app. I understand how important it is to have the perfect solution for your product images, so I’m happy to help out.
I took a look around our App Store and found an app called Image Optimizer by LoyaltyHarbour. This app offers the functionality to automatically compress images to minimize file size, and increase SEO through alternate text and file name optimization. If this interests you, they are currently offering a free plan to test out with 50 images. I suggest checking out the information listed on the app description here to learn more about the features.
Alternatively, the Minifier SEO Image Optimizer by Aheadworks and Image Optimizer by Squirai are some great apps to check out as well. They are free to install, and offer the standard features like image compression and SEO optimization, along with a few additional functionalities that may interest you.
I’m happy to provide some tips and guidance and I'd love to know more about your business! What type of products are you selling? How is your current marketing strategy going with bringing customers to your product pages?
Feel free to let me know if you have more questions!