How to install a Chrome extension from outside of Google Chrome App Store

I'm using an extension for Google Chrome named Eveote Clearly. Unfortunately the extension is not supported anymore by Eveote und hance not available in the Chrome App Store. But I still have it installed in my Chrome.

My problem is that if I install Google Chrome on a new machine, Clearly will not be installed along with the other extensions as soon as you login in the browser.

But I think it must be a way to export the necessary files from the browser instance where the extension is still available and then import it in the newly installed browser instance.

Can you help me how to do that?