ERA-R plugin

Audacity does not come with ERA-R plugin, but apparently it does work in Audacity, see …
https://forum.audacityteam.org/t/plugin-era-r-from-accusonus-not-working/46550/1

#1. I doubt that plugin will cure a loud echo.
#2. I think you have to pay ~$60 to use it after the 14 day free-trial.