Testing Reel Smart Motion Blur in AE - applied to composite image, and to flying creature without a background, before compositing. Settings had to be reduced to avoid parts of the background getting smeared, sometimes a large area for a frame or two. (Look at the arch above, with orange light on it, when the orangish wing goes past - dragged along for one frame.)
Don Carlson applied a free open source motion blur to the composited flying creature as well. Mostly worked, but some odd distortions on a few frames.
Also blurred wings in TV Paint by selecting areas and applying radial blur. This was closer to a real motion blur effect, but labour intensive.
With the swordfight, puppet were in set, so could not isolate puppets from background. RSMB blurred bodies and shield, but sometimes failed to blur thin swords which had moved much further. Possibly it moved so far it didn't register as the same pixels - but that is where you need a motion blur most.
Faults are more obvious when clicking through single frames in QT - it sorta works when playing at full speed in flash.