A phone number can only be linked to one free game
It is not possible to move Battle.net Balance between accounts.
It is not possible to move a Call of Duty account to another Battle.net account
Information on where to update your Activsion Account Email
Information about the Officer D.Va skin from the Nexus Challenge Heroes of the Storm promotion
Information about consolidating Battle.net accounts, and how to play on multiple Battle.net accounts at the same time.
How to attach an Authenticator to your Battle.net account
How to see if your Microsoft Account and Battle.net Account have been correctly linked for Game Pass
Troubleshooting steps for issues while linking a PlayStation Network, Xbox Live or Nintendo Switch account to a Battle.net account