Just about every game I have lists valid resolutions, so it’s possible to do it. Multi-Monitor should have no impact on complexity of doing it. A valid res is a valid res, whatever the desktop supports is a valid res. If you then want to go filter out specifics, then you can do so. Like only 4:3, or only 16:9, or whatever. I don’t see it being a problem. I’m sure there are way more complex blueprint nodes than that.