@MichelRueger suggested the following Idea.
Yes and No,
If your Meraki Network is not to big or you know the Serial Number of the Meraki Device (Switch, AP, MX) you can youse for example Postman and the
This will show you all clients connected on this device for the last Mount.
There is a other way. If you have the Clients attached to spezial Policy Group you can select the "all clients with a policy group " view and then export the list to a XLS File. You will see all clients even if there where not connected more than a mounts.
Hope this will help you.
Regards Michel Rueger
usually the mac address is not part of the columns, so all you need to add this by clicking on the +
It will ask you to select columns, put a tick next to mac address, then it will appear in your columns.
then click on Download as, and choose the format you or XML