What does your ideal workflow look like? Is this something you want do six times a week, 500ml at a time, or batch out into two 1.5l batches?

I don’t have one, but this definitely strikes me as a simple setting for a smart coffee machine. I have to think an Aiden or the like would have this functionality, a sort of extremely long infusion up to the volume of its brewing basket and then a standard release. If you’re asking for specific advice on smart brewers, fair enough. I’d be surprised if there isn’t something with an extra large brewing basket.

I definitely think any decent smart brewer could mirror the immersion flavor profile and intensity even if it can’t go full immersion.

Frankly, my first impulse was to just run a Mr. Coffee (or your current machine) with a manual release valve without the carafe inserted and see if you like what you get when you pop the carafe in at 10 minutes. Temperature control would be weird. Probably too small for your purposes?

I would just buy two Clever Drippers and brew them at the same time. The Switch is more versatile, but the Dripper is exactly the right device for this and cleanup is a cinch. If I wanted a big batch, I’d brew all three simultaneously and plop them one at a time on a two liter vessel.