If US folks are looking for this feature, it can be found on higher end Bosch dishwashers in the US.
I have very hard water and a Bosch benchmark series. The water softener makes a huge difference. I don't want a whole-house softener because I don't enjoy the feel of softened water in the shower.
Everyone I've ever known with water hard enough to be a bother just installs a whole-house water softener, so all the water inside the house is already softened. Seems inefficient to soften only the dishwasher when a whole house system is pretty cheap.
We had a Bosch dishwasher with a built-in water softener when we lived in Lake in the Hills, IL, a suburb of Chicago. The municipal water there (from wells) was extremely hard and it made a big difference.
We now have a Bosch dishwasher in another house in NY state. The water is not hard (it's from one of the Finger Lakes), and the dishwasher does not have a softener, but we like the brand. After reading this story we looked up how to tweak the rinse aid dispenser and turned it down from "5" to "1".
It may be over-softening. Our water felt slimy until we replaced our old unit. The new unit uses way less salt (at least 10x less) and the water feels normal.
If US folks are looking for this feature, it can be found on higher end Bosch dishwashers in the US.
I have very hard water and a Bosch benchmark series. The water softener makes a huge difference. I don't want a whole-house softener because I don't enjoy the feel of softened water in the shower.