Is there a way to filter Elements perpendicular to the View (Section and / or Elevation) direction?
Assuming you are only wanting the elements within the view extents. Could you not just get all element visible in view or do you have elements hidden in the view that you want to get also?
I have a came up with a different solution which works for me i think).
Temporary ‘store’ the needed / wanted Far Clip Offset value in another Parameter.
Set the Far Clip Offset to like 100. Tag the Elements which needs to be Tagged.
Restore the old Far Clip Offset value.
Still want to know IF it is possible though. 
You may can come up with something using the View Direction. That will give you the vector perp to the view. Not sure what the next steps would be, without diving into it. Maybe someone else has input.