So here's the fix I was able to accomplish for this. I had to order SEVEN DIFFERENT HDMI SWITCH BOXES to get this set up to work! Every single one of them, except for the last one, exhibited the following issue: it would show up as "active" to my auto-switching Monoprice HDMI switcher, even with the power off!
Basically I have an 8 port Monoprice HDMI switch for my setup. However, I finally exceeded 8 HDMI devices, and there aren't any HDMI switchers that have more than 8 ports. So my idea was to plug a 4 HDMI switch INTO input 8 on the Monoprice HDMI switch (essentially daisy-chaining them). So I would now be able to have 11 HDMI devices hooked up.
I also figured this would have the added benefit of the Framemeister not constantly sending an "on" signal to my Monoprice switch. This was the most annoying thing ever. Any time I rebooted a system, the damn thing automatically switched over to the port the Framemeister was plugged into. I figured with the 2nd 4 port HDMI switch powered off, the Monoprice switch would no longer constantly have an input that was always "on". I was extremely wrong!
Seven different 4 and 5 port HDMI switches STILL sent a signal to the Monorpice switch, even when the 4/5 port switch was powered off!
I kept returning them to Amazon over and over again, until FINALLY I found one that when powered off, it no longer sends a signal. It was this one:
https://www.amazon.com/gp/product/B08H83CSTL/
So now I have the Framemeister plugged into that. My Harmony is set to only turn that 4 port HDMI switch on whenever the proper device is selected. So no more annoying auto switching from the Monoprice switch.
This was such an immense amount of work just because the Framemeister doesn't properly know how to go to sleep, but at least I finally found a cheap workaround. So if anyone else is having this problem ever, this is the switch to get!
https://www.amazon.com/gp/product/B08H83CSTL/
Hope this helps someone else out with both the annoying Framemeister issue, AND the need for more HDMI ports!