In my opinion 4-4-2 is quite different from 4-2-3-1 because in 4-4-2 we have two classic wings on the sides and two static strikers in the middle of the area, in 4-2-3-1 we have only striker in the middle of the area(and so he have to move troughought the spaces of the area), two wings that play with inverted foot and an advanced midfielder with different skills and characteristics (a playmaker, a box to box midfielder)
4231 defensive
In my opinion 4-4-2 is quite different from 4-2-3-1 because in 4-4-2 we have two classic wings on the sides and two static strikers in the middle of the area, in 4-2-3-1 we have only striker in the middle of the area(and so he have to move troughought the spaces of the area), two wings that play with inverted foot and an advanced midfielder with different skills and characteristics (a playmaker, a box to box midfielder)