According to Battle.net the only way to opt out of showing your real name is to disable RealID entirely :(
*************************************** Can I opt out of any Real ID options?
Yes. By default, your real first and last name is visible to the Real ID friends of your Real ID friends. However, you can choose to not appear to these "friends of friends" by toggling the option in Battle.net account management (under the "Communication Preferences" section). You can also choose to not be included in "Add Facebook Friends" search results. You can also disable the Real ID feature entirely. *************************************
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According to Battle.net the only way to opt out of showing your real name is to disable RealID entirely :(
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Can I opt out of any Real ID options?
Yes. By default, your real first and last name is visible to the Real ID friends of your Real ID friends. However, you can choose to not appear to these "friends of friends" by toggling the option in Battle.net account management (under the "Communication Preferences" section). You can also choose to not be included in "Add Facebook Friends" search results. You can also disable the Real ID feature entirely.
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