That's called a second dishwasher: one is for taking out, the other for putting in. When the latter is full, turn it on, dirty dishes wait outside until the cycle finishes, when the dishwashers switch roles.
I thought about this and it gets even better. You do not really need shelves as you just use the clean dishwasher as the storage place. I honestly don’t know why this is not a thing in big or wealthy homes.
