Muscovy females are small. I looked at the pics again and as long they are close in age, it may be a girl. Up to you if you decide to keep it but if it is indeed female, you could just use the eggs or see if she makes as good of a broody/mother as most scovies do.
.... i don't know nothing but that looks like a girl to me, i mean, scovy drakes are so big and... male.