Code requirements will be the same as for any plastic insulation.
Probably the largest negative is that the cavity would require complete closure. The gaps at electrical boxes are large enough for the beads to leak out, even the cable openings in the romex boxes. If there is a hole in the sill, the stuff will drain through it.
There are separate compartments that store the beads and the beads move through pvc pipes with positive/negative pressure created by vacuum motors.
My house has beadwalls going down the south side. Most of the south wall has Trombe walls inside the beadwalls. The glazed wall has 8@ 4" X 12' windows and 2 @ 4' X 8'.
My son, currently doing his architecture internship, was in class a few years back when the professor described the beadwall system. He said he believed there were no working systems in existence. My son explained that our system works just fine.