Existing scrapers: AddonsScraper.py, FreeAMO
AddonsScraper.py
The current AMO scraper is AddonsScraper.py that generates the "Tools -> Add-ons and Themes" list for Icedove and IceCat: https://trisquel.info/en/browser-plain
FreeAMO
I wrote FreeAMO a few years ago, that is intended to replace AddonsScraper.py. It's used to generate MediaWiki pages that can be imported.
It's officially part of the Directory Import Project (that both I, and Ruben, are members of) used to update the Free Software Directory (aka the Directory)
However, we have not used FreeAMO to update the Directory yet, and FreeAMO must problaby be updated to functioning with the AMO API. But we had plans to do so in the future when IceCat (Tools -> Add-ons and Themes) will replace the addon-page that is using trisquel.info, with Collection:IceCat WebExtensions.
However, IceCat is currently unmaintained for Trisquel.