Depends on the light, in full sunlight, it might be, but wear a black balaclava and problem solved. Some technical details:
the visor is a plexiglass, it has 20% light transparency. So you will have a pretty good sight from it, but yeah, there will be some cases when your face could be seen, flashlight on photos, sunlight, etc. Normally inside a room or a convention it's not an issue. But you have to see out somehow, and the eyes should be visible (if it's the led eyes), so that is a compromise you have to make.