Devices and systems for exchanging properties between at least two fluid streams and related methods may include a valve device comprising a valve actuator configured to move at variable rates in order to selectively fill and empty at least one tank. Devices for exchanging properties between at least two fluid streams may include a valve device comprising staggered and overlapping openings positioned along a path of a valve actuator. The staggered and overlapping openings may be configured to selectively and gradually place an inlet in communication with at least one tank.