There is a quick and easy way to determine if a linear polarizer affects metering. (I have no knowledge re: autofocus)

Point the camera (preferrably mounted on a tripod) at a light colored, somewhat textured and indirectly illuminated wall. Rotate the polarizer while watching the metering indicators in the viewfinder. Because the light reflected from the wall is essentially unpolarized, rotating the filter will have no effect on the light reaching the lens. If the metering indicators change then the light reaching the sensor is being affected. If the metering stays the same you're good to go.

FWIW both my Nikon FM and Contax RTS II work fine with a linear polarizer.

Cheers,
Mike