digitalpoint

A simple and lightweight plugin that can automatically convert Media images to the WebP or AVIF image format as they are uploaded. Includes the ability to add watermarks to uploaded images. Support for optionally retaining backups of the original image.
<ul>
<li>No cost, no subscriptions</li>
<li>No reliance on transmitting your images to a third party server</li>
<li>Support for multisite networks</li>
<li>No third-party PHP libraries are used</li>
<li>JavaScript is native (does not use jQuery)</li>
</ul>
Modern image formats
AVIF images are <a href="https://web.dev/articles/compress-images-avif" rel="nofollow ugc">~50% smaller than JPEG images</a>, and WebP images are <a href="https://developers.google.com/speed/webp/docs/webp_study" rel="nofollow ugc">~30% smaller than JPEG images</a> with the same image quality.

Image Shift – Convert, optimize and watermark AVIF & WebP media images

Convert and/or watermark uploaded media images to the WebP or AVIF image format automatically.

giuliopanda

Bulk images allows you to optimize images uploaded to wordpress without creating unnecessary copies of the upload folder!
Warning: the plugin overwrites images. 
Later the plugin tries to update links to images in articles and metadata, but it may happen that these need to be recreated. Other plugins that optimize images generally duplicate all images and create complex overlays to manage their systems. This plugin is designed to keep sites with the original wordpress structure, but it may require a little more work later. But I believe this work is rewarded by better final quality. 
If anything goes wrong anyway you can go back with the restore button.
<ul>
<li>You can resize all images with just one click.</li>
<li>You can convert images to webp.</li>
<li>You can optimize images by choosing quality.</li>
<li>You can change the name of the images</li>
<li>It is optimized to speed up the bulk process. 1000 images take a few minutes on a normal server.</li>
<li>You can enable the option to optimize images when uploaded to the server.</li>
<li>Allows you to decide the maximum size of the images and the quality in which they should be compressed.</li>
<li>Adds to media-library (list version) the possibility to select the images to be optimized.</li>
<li>Through graphics it allows you to monitor the status of the images on the server.</li>
<li>Ability to use specific hooks to customize optimization options.</li>
<li>You can restore and go back to the original images.</li>
<li>
You can remove the original images if you have space problems.
The GitHub repo can be found at <a href="https://github.com/giuliopanda/op-bulk-image-resizer" rel="nofollow ugc">https://github.com/giuliopanda/op-bulk-image-resizer</a>. Please use the Support tab for potential bugs, issues, or enhancement ideas.
</li>
</ul>
<h3>Credits</h3>
The Bulk image resize was started in 2021 by <a href="giuliopanda@gmail.com" rel="nofollow ugc">Giulio Pandolfelli</a>

Bulk images optimizer: Resize, optimize, convert to webp, rename …

One of the few plugins that overwrites images while keeping your website clean

Image Shift – Convert, optimize and watermark AVIF & WebP media images vs Bulk images optimizer: Resize, optimize, convert to webp, rename …