AFAIK I don’t think that the Yamaha “Vocaloid 4 Editor for Cubase” is available for Mac.
If you have a look at the description of the product at yamaha.com there is no mention of Mac, only Windows.
Synthesizers & Music Production Tools - Products - Yamaha - United States
The description of the “Vocaloid 4 Editor” at the Vocaloid Store does not mention either Mac but Windows only.
On the other hand several Vocaloid Banks are available with another Vocaloid editor than the Yamaha one, and they are Mac compatible.
For example “Megurine Luka V4X” comes with “Piapro Studio” which is a vst that works with Windows as well as with Mac
You can get “Megurine Luka” at Big Fish Audio:
BTW if you are really interested into Vocaloid you will have to live with the fact that some of the products, though in some way at the end available, are not so easily available as other Music Software.
Best regards