An assembly set for transmission devices for motor vehicles. Each of the transmission devices has an input shaft which can be operatively connected to a drive device of the motor vehicle, as well as a first output shaft, and a second output shaft, and has a spur gear differential transmission designed as a planetary transmission, via which the input shaft and an intermediate shaft that is coupled or can be coupled to an electric machine arranged coaxially to the input shaft are coupled to the first output shaft and the second output shaft. The electric machine is coupled to the input shaft in a first shift position of a shift device and to the intermediate shaft in a second shift position of the shift device.