First off, it seems like you have some sort of mechanical problem between the 35 and FE B, seems likely it may not be engaging the meter coupling lever correctly. The aperture ring should not ever be tough to turn, and if it is, find out what's wrong before turning it more.

Then to get a good test of the metering, first you should either use the same batteries in both cameras or else get a set of fresh batteries for both cameras.
Next, meter some evenly lit featureless surface like a wall so that it fills the frame with both lenses, and meter the same area with the hand held meter (reading off the wall). Make sure there are no shadows in the area you're metering. Better yet, use a grey card.

Incidentally, if by "a mix of old/used generic batteries" you mean that you have mixed battery types, brands or two batteries that have different states of charge (like one newer than the other), get them out of the camera asap, as you are inviting them to leak. (the stronger of the two tries to charge the weaker one causing it to leak).