Reports

I would advice to use a different field that can be retrieved with either the Entra ID connector or Office365Users, but if this is the only option I think you could map the description field to onPremiseExtensionAttributes

And then retrieve it using Graph APIs user endpoint

https://graph.microsoft.com/v1.0/users?$select=onPremisesExtensionAttributes

This is the response. As you can see there's 15 free attributes, if non are mapped already

"value": [
    {
        "onPremisesExtensionAttributes": {
            "extensionAttribute1": null,
            "extensionAttribute2": null,
            "extensionAttribute3": null,
            "extensionAttribute4": null,
            "extensionAttribute5": null,
            "extensionAttribute6": null,
            "extensionAttribute7": null,
            "extensionAttribute8": null,
            "extensionAttribute9": null,
            "extensionAttribute10": null,
            "extensionAttribute11": null,
            "extensionAttribute12": null,
            "extensionAttribute13": null,
            "extensionAttribute14": null,
            "extensionAttribute15": null
        }

Regarding the licensing issue, graph api can actually be called from canvas apps using the Office365Groups connector. Here is a good tutorial from Reza

Tried it in app and it was successful

Set(glbTestGraphCall, Office365Groups.HttpRequest("https://graph.microsoft.com/v1.0/users?$select=onPremisesExtensionAttributes", "GET", ""));

Got the same response in the monitor as it was in Graph explorer, so you could use these attributes in the app as well

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