Office 365 group created from which Source ( Teams, SharePoint, Yammer, Planner, PowerBI)
There is no current property under group that can identify the source of Site collection created as part of Office 365 group. As an admin when we want to clear the site collection. We don't have any visibility from where this site collection has been created. Only way is to check Audit Log and check each item for the source of creation. This option is limited to only 3 months of Audit log data.
We have enabled a new property on the group object called CreatedByAppId. This property is currently available under the /Beta endpoint of Microsoft Graph.