I’m sorry, but Zammad doesn’t provide webhook functionalities to trigger a url call to another system.
You can, at any time, poll the Zammad API forusers that have been created in a specific time span.
Not sure if that will help you.
The question and goal sounds similar to one of your earlier posts:
I’m afraid my answer hasn’t changed much since then.
For completeness, these documentation pages should help you for that goal: