There's two issues I've noticed when using this setting combined with mouse input for parries and attacks.
1. If I hold stab for example and try to parry any other direction, it will still parry down. This makes it annoying to cancel an attack to a parry.
2. If I perform a feint and then hold...
If you manage to hit someone and they don't parry, you should get a chunk of stamina back like you do in Mordau. Seems like this is the component that's missing which is making everyone stam out all the time.