I trialed Auto Latch, might be better named Not Latch. Yeah it holds notes, but not all of them. It seems I have to hold it for long enough, but not too long, or something. When it holds a note, and I hit a different key, it'll play the new note, but as soon as I let go, it goes back to the previous note, I hit it again, it'll usually latch onto it. Not always though. I have to use Poly latch, use 2 (or more) steps. It isn't quite made to do what I want it to do. I am sure it is perfect at what it is designed for, as a player.
I just need a device that allows me to plug in more than one device, holds a note I play, can send several inputs to one output as I switch them, one at a time, and I can switch to a different input.
It can even have multiple outputs, but at least one output.
I have PongaSoft AB12 audio switch, but it doesn't hold notes and only switches between banks of inputs. So if I only need two instruments, I am fine.
Yes I'll use Auto Latch for now. But it isn't the best. It is kind of like using a car as a boat, you have to do all kinds of stuff to it to make it float.
After typing all this, I tried using the Reason Mixer 14:2 or for economy, the Line Mixer 6:2, and a MIDI track for the devices. Just mute all the devices in the mixer, then hit Solo for the one I want to listen to. It is a pretty good fake for what I want.
If what I am looking for doesn't exist, does anybody want to make one?