I have this farm with multiple layers that needs to change to make it compatible with 1.14.4 everywhere there is a blue ice block I want to place a layer of snow on top of it. I found the overlay command however this doesnt work as there are multiple layers in this farm. Is there an easy way to put a snow layer on top of every Blue ice block?
Using offset masks is the correct way to do this with WorldEdit.
If you want to replace every block above blue ice with snow, use
//replace >blue_ice snow