Jonas is correct, I think the customer may misunderstand how MPSK is implemented, it's essentially the same as a standard PSK, but can be unique per device. At our organization, we leverage MPSK for vendors to connect their devices that don't support 802.1X authentication, by doing so we can limit which devices can use a key, provide unique keys per vendor, and prevent exposure of the actual key outside our organization. In this case, WPA2/WPA3 Personal does not require a username, only a password which is derived from the RADIUS response after the MAC auth takes place. Be aware that for 6GHz/WPA3 - MPSK is not an available option (yet). If your customer is looking to leverage a unique username and password, ClearPass and Central have options for both LDAP/AD accounts or local accounts.
In my opinion, if a device supports 802.1X authentication in WPA2/WPA3 enterprise, I would go that route, but if the device does not, MPSK would probably be valuable assuming it's not a WPA3/6GHz SSID.
Alternatively, in the ClearPass service, you could reference the "Authentication Username" and "Connection Client-Mac-Address" to combine in the policy which would sort of accomplish the same idea without the MPSK being involved.
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Michael Haring
Sr. Network and Communications Expert
Lehigh Valley Health Network
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