You can configure posts image source using a simple yet powerful admin interface. 
Just choose a post type of your need (including WooCommerce products!), choose filtering options or specific post IDs, and you are ready!
After choosing what posts to use, you need to decide where to take images from:
- Featured post images can be taken (which is pretty sensible default for most cases)
- Or all the images attached to the post can be used if you want to show everything.
And the last step: choose what data goes where:
That is it!