I am using CiviCRM 5.56 (will update soon) on WordPress 6.2.2. I have created an event using CiviEvent. I would like to provide access to other organiser to at least see data of participants (both the participant registration data and the data of the related contacts) but limiting other thing he could do in CiviCRM and the WordPress (so especially not admin in WordPress).
I have tried ACL but in no combination it have worked yet. Specifically, setting ACL by "event" only have effect on access to the event info and registration page, but not on seeing and managing participants data.
For now I have added the required permissions (access CiviCRM backend, access CiviEvent, edit event participants) to some WordPress role, and than assigned that role to the other organiser. It basically works but it is sub-optimal, because it limits how we are using those roles in the WordPress. I could define new WordPress roles and assign multiple WordPress roles to WordPress users but I prefer to not do that, because WordPress is more fragile when users have multiple roles.