I am loathe to open yet another thread about WooCommerce image sizes, but I can't find a single, reliable source of information from within ThemeCo on how to address the various issues that seem to arise when upgrading to the latest version of Pro and WooCommerce.
Since upgrading we have lost access to the gallery functions of being able to skip back and forth on product images, and the image thumbnails are now positioned to the right of the main image, instead of underneath, and are cropped to about 21px x 21px.
Changes to the image dimensions made anywhere in the Theme Customiser don't stick, and there appears to be nowhere else that we can adjust these image sizes that actually works.
You can see the current live site here: https://wordpress-85897-680649.cloudwaysapps.com/product/coco-skirt/
And the staging site here: https://soulsonglife.com/product/coco-skirt/
The modal that pops up on the live site is preferred, as it provides the opportunity to see the products more closely.
note: the live site is built on Genesis with a custom skin; the staging site is built on X Pro. We have inherited this site with zero documentation, and are still unwinding a bunch of hacks the previous developers made in the css and the functions files, but cannot isolate the cause of this particular issue.
We have also NOT yet done any sort of a thumbnail Regen due to the size of the site. If that's the right answer, then we will obviously do it, but given how many images, and how long it will take, we didn't want to execute on this unless it was the correct answer.