Depends a bit on the age of your car. The early C8s that used MIB-2 can be programmed with a variety of tools such as OBD11, Carista (Limited), VCDS or through the purchase of dongles from Kufatec, but the switch to MIB-3 saw Audi also lock down what could be done in term of enabling functions such as Traffic Sign Recognition, presumably as Audi hoped to derive revenues for this additional functionality through the built in Store (sadly not activated in the UK). Sarah1331 on here has been able to activate a number of functions even on MIB-3 cars using VCP (
https://vcpsystem.com), so would suggest looking at that as an option