I haven't tested this but in theory you could use outbound codes, you'd have your usual codes (e.g. for customers) where you set the calling line identifier as the default outbound line (the one you want customers to see)
Then you add a code for internal calls and set the Calling line identifier as "Use agent default calling line ID" but then you'll need the agent default calling line ID (user profile) to be something meaningful - as far as I can tell you can only use VCC channels and not agent numbers but at least this could get you halfway.
VCC admin is being updated by 8x8 at the moment so it's possible the feature could be added - this definitely seems like something that would be useful in the new "micro VCC" product they're developing so you never know!
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David
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