White skin a recessive trait, so if a white person had children with a black person, would all of their children be black? no matter if the black person was the mother of father? or does that matter too?

If a white person had children with a black person, not all of their children would be black, but majority of them would. There is a 75% chance each time the parents have an offspring that the child will be black. It would not matter if the black person was the mother or the father, because either way they are the dominant trait, and according to the punnet square, that is all that matters and that will effect the outcome.