Import enrollment devices via Graph API

To import devices directly via Graph API you can send a body to an API endpoint that contains the serial number and the hardware identifier.

DokumentationUse case

To make an automation which imports devices automatically into Intune enrollment devices you can create an Azure Function that will then import the device id automatically to Intune without any user interaction or permission management. This action will be performed in the context of an app registration.

PowerShell script

This 

{
  "@odata.type": "#microsoft.graph.importedWindowsAutopilotDeviceIdentity",
  "groupTag": "<yourgrouptag>",
  "serialNumber": "<yourserialnumber>",
  "hardwareIdentifier": "<yourcomputershashid>",
}

Corresponding Microsoft documentation

Create importedWindowsAutopilotDeviceIdentity - Microsoft Graph v1.0 | Microsoft Learn