Can’t find any resources anywhere…
Hmmm not sure. Never done it myself. Let me ask the tech team and get back to you on this one 
This won’t be possible in WeWeb. While you might be able to design in the editor, you won’t be able to export it in the format required webstore, and nor will you get a manifest.json file for the extension, which is required. Moreover, the site will be deployed on a domain in WeWeb, whereas for a Chrome Extension, you’d want to either upload on Webstore or create a downloadable crx format - both of which aren’t natively supported in WeWeb.