Oil at PVC Fitting?

I see one with a filter/breather on top and one without. Since it has a breather, will air still be drawn in through the other valve cover that has a breather?

My bad. You don’t want one with the breather/filter. You want to pull air from only one source, so the air that the PVC is pulling comes through that breather, down through the crankcase and then out the PCV valve, into the separator and then back into the engine.