Dunno how well WFX handles/works on multi monitor setups, but here it doesn't 'perform' 100%
I have 'Enable screen edge windows resizing' unchecked in the config

But it only applies to the main monitor. As soon as I move any window near the edge of secondary monitors, they auto resizes.
Latest WFX from SDC
64 bit Winblows 7
As far as I know this 'feature' isn't enabled/disabled anywhere else or in any other application. I haven't seen it anywhere else than in WFX.