The Swan Goose is distinguishable by the orange or black knob on its beak, more swan-like than goose, and by the broad dark brown line on head and back of neck. Larger than Canadas and Greylags, the domestic Chinese goose is descended from the rare wild Swan Goose of China, native to NE China, SE Siberia and Mongolia.
The domestic breed in Europe/North America is split into two types: the China/Chinese Goose (as the "Chinese Grey" above), slightly smaller and usually without chin dewlap, and the African Goose, which also comes from China not Africa and is larger and has heavy chin dewlap as below; both domestic species can be brown with black (usually) or orange beaks, as in the wild, or white with orange beaks (through breeding).
This goose is likely to be a hybrid "African" China Goose.
Male (above) and female have a similar appearance, but the male is larger, has a more prominent knob and less undercarriage (see first row 2nd photo, male on left, female right)
Showing the distinctive broad vertical dark brown bar on the back of the neck