For those like me from the future internet, I’d like to re-raise the original question given the update to OpenSprinkler since, such as the DC controller and Latching versions.
Specifically, as I’m automating a solar powered off the grid setup, I’d love to use motorized ball valves with OS. The two-wire auto-return in theory should work with the standard DC OS version, as these spring to close when de-energized. I’m curious if the DC latch version works with 3-wire valves, which require a change in polarity to re-close? It may however be the case that latch control is too different in the specifics. I’d be interested to hear what capabilities around motorized ball values now exist.