I've always been bothered when I have to upload an image to a website with a strict file limit (like 50KB). The old nautilus-image-converter I used didn't have this feature.
So, I forked the legacy package (v0.3.1) . My new option just appears right inside the existing "Resize Images" dialog, alongside the original "Scale" and "Custom Size" options. It uses jpegoptim for JPGs and imagemagick for PNGs.
It's a simple fix, but I think it will save time for many people. I've tested it on Pop!_OS 22.04 (GNOME 42) and it works perfectly. It might not work for gnome 45 and above
I'm sharing it in case it's useful to anyone else. Let me know what you think!
GitHub Repo: https://github.com/Ameen-Sha-Cheerangan/nautilus-image-converter-legacy/
More info is in the README.md in github, reviews and suggestions are welcomed.