This is repo is a utility designed to make converting any image into a webp format easy. Its currently only working in windows. It requires nodejs and npm to be installed. After installation you should be able to right click on any file and select an option to 'Convert to WebP' which will prompt you for quality options.
Download repo into location that has no spaces
Run:
npm i
Then to install to the right click menu in windows:
Open the add-to-context-menu.reg and update any paths for your system, note the \ escaping
Run the add-to-context-menu.reg script and it should be added to your right click menu for all file