No, the DualSun Wave panel is not drainback compatible.
It should be noted, however, that the main reasons installers prefer a drainback system concern the overheating and subsequent denaturation of the glycol.
With DualSun Wave panels, this problem is eliminated thanks to the relatively low stagnation temperature which provides intrinsic protection against overheating of the installation. These drainback systems would not provide additional protection in this case, which is why the DualSun Wave was not designed to be drainback compatible.
On the other hand, the DualSun Spring panel, designed in part for swimming pool heating installations with direct water circulation, is drainback compatible in order to facilitate flushing the system in winter.