Informatiza

Sutolix

Automatically convert all images (png and jpg) sent to the WordPress library to webp.
ATTENTION: The original images are not kept, when sending an image it will be as if you had sent a webp from the beginning.
Features include:
<ul>
<li>Set conversion quality.</li>
<li>Set the maximum width/height of images. If an image exceeds the defined value in height or width, the image will be resized to the defined maximum.</li>
<li>Ignore images that have a certain name in the file name</li>
</ul>

Webp Transformer

Convert images from library to webp and resize them during upload

huiz

The plugin affects the uploaded image while it is uploaded. Straight 
after it is uploaded, it it resized physically to the given width. 
There is no original image left, nor made a backup. Also EXIF infor- 
mation is lost.
A lot of WordPress users or developers who use WordPress as a CMS 
and want to configurate it for easy use, would like to have an option 
to resize uploaded images. Some images come straight from digital cameras 
and exceed 4000 pixels in width. So it would be nice to reduce that to 
the max width you use inside your WordPress theme.
If you want to keep control about perfect sharp and resized images, you 
better use photo editing tools on your computer, not a script like this.
The plugin uses a class originally from Jacob Wyke (www.redvodkajelly.com).

Resize at Upload

This plugin resizes uploaded images to a given width.

Webp Transformer vs Resize at Upload