While this skiing trip in Japan does require some experience with backcountry skiing in variable conditions, the difficulty scale isn’t that high. Most of the ski touring terrain in Japan is mellow, the slopes aren’t that steep, and the altitudes are pretty low.
You will be skiing in the 1300-1500 m range, downing mostly intermediate runs with the occasional advanced pitch, and doing plenty of treeline skiing. You have to be comfortable with multiple hours of skinning, diving into deep powder, and navigating between trees to fully enjoy the terrain.