Hello,
Image sizes can now be configured under the Customizer. Go to Appearance > Customize > WooCommerce > Product Images: https://pasteboard.co/IFIFFrb.png
Here you can set the Main image width, Thumbnail width, and Thumbnail cropping.
Image heights have intentionally been removed, as they are calculated automatically based on your settings. It’s worth noting here that your main, or “single”, product image no longer has any crop settings; they will always show uncropped.
As soon as you make any changes to these settings, WooCommerce will automatically generate the new image sizes. This may take a little while to process, but it runs in the background.
Best Regards.