Hi @WouterT ,
After some research, there's no such like NWC API exposed publicly that can give action's configuration for a specific workflow definition. However, you can search for all workflow's instances that implement a "Call a workflow" action with a specific label. But even so you can have 2 workflows that implement the "Call a workflow" for the same component workflow but with a different label. So the label is not reliable.
From Nintex Analytics, you would be able to list all workflows that include an action "Call a workflow" as shown below :
There's no option/tool to know which workflow called a specific workflow other than from the workflow designer.
From NWC API, you could get the lists of workflows instances that include an action "Call a workflow" with a specific label :
Possibly, you can have 2 workflows that include a "Call a workflow" action for the same workflow component with a different name. The label is not reliable.
Regarding the Connectors and Datasources, same. There's only API to list them but not to know the workflows that reference them.
Regarding "certain actions", you can definitely use Nintex Analytics.
I would suggest to request the features within Nintex Uservoice.
Using an RPA solution could be an option but really challenging. I did not try that option.
Hope that helps, ^^