I don't see any basis for accurate comparison, there is too little information given. The manuals give even less information than the blurbs.
Given the size of the brushed universal motor appears identical the power output is probably very close to being the same. From the linked reference below, the power factor of universal motors is given as the range 0.7 to 0.9, with the lower figure applying to the maximum power input. Image below from here
The effect of armature inductance will be higher at 60Hz than 50Hz so there may be some slight difference as a result of that, even with the motor designs fully optimized for each situation.
There are instances where the 240V appliance has higher power capability because of outlet limitations for the North American market (eg. kettles where ~3kW is possible in Europe) but that does not seem to be clearly indicated in this particular case.