Not intending to suggest any rubbish, just adding my tuppence worth.If I remember my basic physics you can replace any a force acting from any point by a force acting from any other point plus a moment acting.
The forces do not have to be equal, if they are not you would simply get an additional force acting through the rotation point which would not affect the pitch up (or down) as there is no moment from it.
Thus the pitching moment will not be either way if the forces are not equal, it can be calculated, and as was said, depends on the a/c type.
BTW it would make sense to calculate the effect of combined forces by shifting them to the vertical CG as you said.
Regards
JW