I was able to migrate a Google Voice number and history from one @gmail.com to another @gmail.com - IIRC there was someone on Google support forums who I messag

I was able to migrate a Google Voice number and history from one @gmail.com to another @gmail.com - IIRC there was someone on Google support forums who I messaged with and after validating accounts they put it in some queue or something. IIRC a day or two later it was all there. Magic.