Hello MMoss,
That is not possible, at least currently, please take a moment to submit this wish by logging in to your dashboard and clicking the Make a wish button.
You can, however, pre-configure network policies for client devices in wireless and combined networks, prior to those devices connecting. In order to apply a network policy to a client device, the MAC address of this client is needed ahead of time
https://documentation.meraki.com/MX/Group_Policies_and_Blacklisting/Pre-configure_Network_Policy_for...
This only works if your network type is wireless or combined type.
Cheers! 🤘