Why would you need 6 different models running across three providers? Just have a single one running, then you avoid all this nonsense around locking.
And this is ultimately pointless, because it’s just a shitter SQLite. It’s nothing new. If you’re going to build something big like this, there needs to be a real business case
You could already slop out a replica of SQLite if you wanted. But you don’t, because of the effort it would take to test and maintain it.