Dynamic/Private Pre-Shared Keys (DPSK/PPSK) to provide a unique PSK per client/user is a Feature Request pending development. Sorry I don't have a time frame. But please do reach out to your local Cisco Meraki reps and have them add your account into the FR in our back-end system to help prioritize with the MR PM team. I have already upvoted the FR myself with some input from some of my own customers.
We don’t have an explicit “upvote” feature or feature request process here on the Meraki Community, but the more kudos a post gets, the more likely it is to get attention from our team. The official feature request processes are via “Make a wish” on the Meraki Dashboard and your account rep (who I believe can upvote the request in our internal system on your behalf).
Caroline S | Community Manager, Cisco Meraki New to the community? Get started here
As @CarolineS mentioned the upvote is on our internal system, and there have been several upvotes, including my own. Get with your local Meraki team and have them go to the Feature Request in our internal system, not only to upvote it, but to add your account/opportunity to the list with several others. They will be able to find it easily, it's actually called "Dynamic / Private Pre-shared Key DPSK/PPSK". Or PM me with your contact info and I'll add it to the FR.