Changing Trello profile visibility
Right now, there isn’t a way to make your Trello profile private.
Because Trello is at heart a social collaboration app, we took our cues from the major social networks like Twitter, where you can easily search people on the site, but cannot see anything more about them than what they choose to make public. This means that your name, avatar, and bio show up publicly, but not your email address.
You can change your account details at https://id.atlassian.com/manage-profile/profile-and-visibility. If, as you make changes, you’d like to check up on how those changes appear to the public, open an incognito window or log out and visit https://trello.com/you. That will allow you to see the public version of your profile with the visibility settings you have in place.
You can learn more about how to update your profile and visibility settings here.