https://eu.battle.net/support/en/article/42673
Cheating

You are responsible for how you and your account are represented in the game world. Cheating in any fashion will result in immediate action. Using third-party programs to automate any facet of the game, exploiting bugs, or engaging in any activity that grants an unfair advantage is considered cheating.
Exploiting other players is an equally serious offense. Scamming, account sharing, win-trading, and anything else that may degrade the gaming experience for other players will receive harsh penalties.
https://www.blizzard.com/en-us/legal...ense-agreement
2. Blizzard’s Ownership
Vii. All Accounts, including the name of the Account and any Battle Tags associated with an Account. All use of an Account shall inure to Blizzard’s benefit. Blizzard does not recognize the transfer of Accounts. You may not purchase, sell, gift or trade any Account, or offer to purchase, sell, gift, or trade any Account, and any such attempt shall be null and void and may result in the forfeiture of the Account;