edit: I see you’re using Gandi mail, that should be adding an email redirection from fosdem2019 to the Discourse email. Active immediately
Unless there is a bug, it is possible to reply to topics via email. So we could also probably define a kind of mailing list the way you suggest. But, as I mentioned in another topic, I’m struggling with OVH at the moment and not very motivated to immediately explore technical things.
Since the email POP3 is already configured, it does not require any change in the server setup, just the Gandi mail redirection. If you can do this, the email-in will work right away for all the aliases pointing to the POP account.
email@example.com is now an alias of firstname.lastname@example.org, would that work?
You’re good at teaching new and useful discourse features: thank you!