The questsion was about the copyright in the footer. Your manual is describing how to change this for rebranding purposes:
But we don't want to hurt aspects of legality. Do we need to change more or will we need a special license?
Customers can remove or edit the copyright section as it allows the customer to make the changes while creating the website.:
Footer. This is the lowest area where the company name, contact information, or a copyright notice are usually placed. You can do the following to the footer:
Reduce the footer height to 25 pixels by removing all elements from it.
Change the footer width from the default size to 100 percent, so that it is expanded to fit the page width.
Parallels copyright on the footer of WPB theme can be replaced with the name of the website or business name. Additional license is not required.