The Voclaoid 2 software comes with all Voclaoid 2 voicebanks. They can in turn be imported into Vocaloid 3 as well.
However, the issue with the Appends is that they are expansion packs and therefore need the original version of the software. So Miku Append needs the original Miku pack and the Kagamine's need the original Act 2 pact (since it replaced the very first voicebanks).
It might be worth waiting for the updated Vocaloid 3 versions to be released since Miku and co are being updated soon.