The software updater does not seem to find Microsoft Edge. Any comments / advice / help on that?
I don’t even know if it is supported since it is relatively new, isn’t it updated through windows update.
It certainly is. The Avast Software Updater isn’t meant to update all things running on your computer. 
I ask because Avast did provide updater access to Internet Explorer.
I believe it is because win10 and edge is more tightly controlled.
That’s no longer the case.