We are a small team on the free plan. I'm the site admin and everyone else have Site Access permission. While some of the team can change Reporter field on a ticket, others are unable to. I tried from the admin console to log in as the user who is experiencing the issue and was unable to do it. I've assigned these users "Trusted" role and still didn't work. (To clarify, I manage users from the from the User Management section in the Admin console and not from the Project since managing users on the free plan can be done only in the admin console.)