Hi @burusa1
I hope you’re well today and thank you for your question!
With images that are stored externally:
1) bulk-smushing option might work if those external images are “copies” so there are still locally hosted images im Media Library – those local ones can be smushed but whether optimized images will then be used on site or not that depends on how they are offloaded; if the script/plugin that you’re using to offload images doesn’t update them on the external storage “on the fly”, it won’t change much;
Smush has an integration with S3 built-in, via the WP Offload Media Lite plugin so if images were stored on S3 and handled by this plugin, it would work
2) Lazy Load should work as long as images are not loaded “dynamically” (e.g. “injected” via some JS) or not loaded as CSS background images via CSS file (but if it’s inline CSS it should be fine)
3) CDN (so automatic resizing and WebP conversion as well as they are only available via CDN) would require images to be stored locally too (or, again, S3 via WP Offload Media Lite) but these features are currently available only in PRO version of the plugin.
Best regards,
Adam