Hi,
In general action groups are like relies. They do not hold any data on their own. They simply rely data from Azure Alert instance to trigger Logic App, function, e-mail, etc. So triggering action group without having Azure alert data does not makes sense. However if you want to test your Logic App workload you could just trigger the Logic app on your own by providing the format of the data depending on the Azure Alert type or you could use feature like Test an Action Group. That will trigger any of the receivers in the action group by using samples for different Azure Alert types.
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