Channel permissions provide you with the ability to give other users access to your channel via specific roles. Designating roles allows you to choose the correct level of access. Migrate to channel permissions to prevent security risks such as password sharing and minimize other privacy concerns.
If a YouTube channel is linked to a Brand Account, various members can manage the channel from their Google Accounts. You don't need a separate username or password to manage YouTube channels with a Brand Account. A Brand Account can be linked to a YouTube channel but not other Google Services.
First, check if your channel is connected to a Brand Account. If it's not, you can change channel managers, but not owners. To transfer channel ownership, convert to a Brand Account by removing all roles in the permissions set up.