Stop using B designations for platforms, the B5 was the last where they were valid, and then the platform was renamed to PL45. (Passenger car, Longitudinal engine, size class 4, 5th generation.)
There's a reason the Europeans use Typ designations, though.
The car commonly referred to as the "B7" (which actually doesn't exist as a separate platform) Passat is Typ 3C, same as the "B6" (actually PQ46, Q being short for a German word for transverse). There'll be sub-types of that, some of which will apply to earlier, some will apply to later models, as well as different body styles (for instance, sedan versus wagon).
The NMS is Typ 56, and is derived from the PQ46 platform (although with suspension modifications, among other things).
(Also, interestingly, the (PQ35-derivative) Jetta and Beetle, despite being different wheelbases, are both Typ 5C, although with different sub-types. Don't have ETKA open to verify, though.)
Most longitudinal Audis produced today are on the MLB component set (not a platform, but it has some platform-like characteristics), and most upcoming transverse VAG products are on the MQB component set. They'll still have their own Typ codes, though. And, "A7 Golf" is going to be so wrong it's not funny. (For that matter, A6 Golf already is wrong, given that the Mk6 Golf (Typ 5K, for what it's worth) is still PQ35, just like the Typ 1K Mk5 Golf.)