Hi Steven,
Thanks for getting in touch. Events Calendar PRO itself does not have any event ticketing or registration features. However, our Tickets: WooCommerce add-on does allow users to register for events and purchase tickets. With Tickets: WooCommerce, users can purchase tickets and pay in a variety of ways, including offline.
If a user buys a tickets with the offline payment option, the order will show as on-hold in your WooCommerce orders list. You can filter to see the unpaid/on-hold orders, although there is not a built in way to print this list. You can watch a video of the process and read more about how the check-in part works here.
Let me know if you have any further questions.
Best,
Leah