Today I was trying to workout which of our Logic Apps uses each of our function apps.
I can achieve this using a resource graph query in Azure so it runs a query that does a join between Logic Apps and Function apps and then looks in the properties for anywhere where the function app name is mentioned.
Note this will be limited to using the function app connector or possibly using it with the HTTP action.
Hoping this helps improve your governance to make it easy to track these things
resources | where resourceGroup contains "eai" | where ['type'] contains "microsoft.logic/workflows" | extend dummy=1 | extend logicAppName=name | join kind=leftouter ( resources | where resourceGroup contains "eai" | where ['type'] contains "microsoft.web/sites" | extend dummy=1 | extend functionAppName = name | project functionAppName, dummy) on dummy | where properties contains functionAppName | project logicAppName, functionAppName | order by ['logicAppName'] asc