To export Contacts enrolled in an automation, go to Automation > Marketing Automation and click on the needed automation.
Click Options > Settings in the top right-hand corner.
Scroll to Export Campaign Data, select your options, and click Export.
There are three export options:
In Campaign - All Contacts currently in the Campaign
All Time - All Contacts that have enrolled in the Campaign at any given time
Goals - All Contacts that have exited the Campaign for reaching a Goal.
The Contacts will be exported in a CSV file.