You are missing: jpegtran, optipng, gifsicle.

Looks like they are not compatible with your server. See if your webhost is listed here: https://www.ads-software.com/plugins/ewww-image-optimizer/installation/

You can also try installing the tools manually: https://docs.ewww.io/article/6-the-plugin-says-i-m-missing-something

I started to have the same problem after updating. I tried to install the tools manually as you recommended but it didn’t help with the new version (3.2.7) and the problem with jpegtran, optipng, gifsicle is remain.
I had to go back to the version 2.5.3 (the only which I saved on my PC) which doesn’t give me problems.

@styleit: https://www.ads-software.com/support/topic/important-please-read-this-before-posting/