I have my current account Battle.net account (this one) that I play WoW on, which I have phone verified. However, I have an old Battle.net account that I used to play Overwatch on that I lost access to a while ago, but I just regained access to it. Since you need phone number verification to play OW2, can I remove my phone number from this account and put it on the other account for OW2, and then change it back whenever I want to play WoW? Would Blizzard allow this or would they be suspicious?
Yes. As long as you have access to the phone to get the confirmation codes, you can do it. I don’t know how long it takes for account flags to update though - it can have a delay so switching may not get instant results.
Now that I don’t know. Just because you CAN do something, does not mean it is a good idea. I don’t think Blizzard is going to answer you.
If you were to even hope to get a reply, you could try asking on the WoW Customer Support forum. That serves as an Information Desk to answer support questions, guide folks through the ticket system, answer policy questions, etc.