No, with Hermes, return labels cannot be created via an event action.

How do I generate Hermes return labels?

Before the shipping label for OTTO Market is created, the return label for Hermes must be created either manually or via an action in a process.

• Manual creation: The label can be created manually via the Shipping Centre.
• Process creation: Alternatively, creation can be done via an action in a process.

Tip: For more information, see the User Guide of the Hermes plugin.