I suspect that the ANO does not cover them. The HSWA has to have specific amendements laid before parliament to apply to offshore installations and wind farms. The Coast Protection Act also.
However there less than 10 of these things worlswide at the moment and I suspect the report was not much more than attention seeking. If dozens of them start to operate around our coasts it will be something else to look out for. I suspect they compromise the manoeurvability of the ship quite a bit so they are unlikely to pose much of a threat for the short Channel crossings. But areas with less traffic could get to be an issue - having said that simple strobe lights would make a big difference in making the kites and more particularly the tow lines visible.