Magento 2 product image zoom extension by FME is one of the best choice for product zoom functionality in eCommerce sores. It is best suited to provide product zoom functionality over product detail page for product images. Customers can instantly view details of product images by magnifying zoom on mouse-hover and displays images in full screen lightbox once the image is clicked. With this product image zoom extension, you can configure rules and set conditions to apply different zoom option to different products.

You can create different types of magnifiers like:

 - Basic Zoom
 - Tint
 - Inner Zoom
 - Lens Zoom
 - Fade in/ Fade Out
 - Easing
  - Mouse wheel Zoom
 - Window Position
 - Custom Design

 - Light box image preview
 - Set a Mobile view
 - Customize lightbox
 - Zoom Images of Store View or Customer Group

More details & demo here - Magento 2 Product Image Zoom