Hello @murphy
Thanks for reaching out!
Get presence Graph API doesn't support Application Permissions yet. Hence, it is not possible to achieve this using Graph API currently.
Since this feature/functionality is presently not available for Application Permissions with Microsoft Graph API, you can upvote an existing feature request idea, so that it can get more upvotes. This feature request portal is monitored by Microsoft team, and they make the enhancements to Microsoft Graph APIs based on the number of upvotes/API in demand. I will also upvote for you.
Related article: https://techcommunity.microsoft.com/t5/microsoft-365-developer-platform/graph-api-presence-should-support-application-permissions/idi-p/2276109
Hope this helps.
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