As I said a few posts ago, if AOA is near zero (i.e. prop axis aligned with incident airflow) then P-factor must by definition be near zero. Torque (unbalanced torque reaction transmitted by engine mounts) might increase the normal load on the LH main gear, but the relative friction increase is negligible.
So that leaves the slipstream rotation - and on pusher aircraft where there's no flat surfaces in the slipstream, I'm told there's no "torque" to be countered with the rudder. Also, if most of the fin & rudder are below the prop axis, the "torque" reaction is opposite that of a more conventional layout.