Much detailed information is only available in English:
Black Breasted Black Face Fawn should have big orange cheeks, and they should be as black on the belly as possible.
This is a Black Breasted Black Faced Fawn male. Ideally, the breast and belly should be much darker.
Black Face Fawn
Note that blackfaced fawn females can be difficult to distinguish from fawn females. Generally, though, they're a little bit darker in colour between beak and tear markings and on the belly.
The Fawn mutation changes the black and grey pigments to fawn (brown) pigments.
The Black Breasted mutation changes the pattern of the markings.
The Black Face mutation causes the belly and the area between tear mark and beak to be filled with black pigment. Ideally, the belly should be as black as on the picture, but in real life, it is often less black.