I anticipate the size will be the same, and I am sure the number of babies will be the same as well.
The reason this particular morph is rare, is because the baby has to come from the spot on the mushroom where the two colors join.
Most of the babies will come from either the green side or the blue side, producing a mushroom completely of that color.
But if one comes from the exact right spot, you get the split in coloration.