It’s really more of a proxy setup that I’m looking for. With thunderbird, you can get what I’m describing for a single client. But if I want to have access to those emails from several clients, there needs to be a shared server to access.

docker-mbsync might be a component I could use, but doesn’t sound like there’s a ready-made solution for this today.

Yeah, they are ideally the same mailbox. I’d like a similar experience to Gmail, but with all the emails rehomed to my server.