Video EDID pass-through vs emulation for HDMI-only KVMs

I am a bit confused about a level of EDID support required from a KVM to get the result that I am looking for: I want to connect a desktop & a laptop to a KVM as inputs via HDMI, and have one single display connected to a KVM as an output via HDMI.

Now, two points are important for me: first, when a desktop is active, I want a laptop to continue thinking that it is still connected to an external display so that it won't turn on its built-in display. Also, when a switch from one input to another occurs, I want a display to think that during the switch it continues to maintain an uninterrupted connection to a device so that the switch will be like changing input select in display's settings - and not like physically disconnecting one device and then connecting another (since in case of an input select change, the change occurs in a couple of seconds, while in the case of a physical disconnect/connect, the monitor starts displaying a message 'HDMI no signal' and even if you immediately connect a device again, it takes ages for a display to start displaying).

Now, if I know that a KVM supports EDID pass-through but not EDID emulation, does it mean that it will be able to do what I want, or do I specifically need KVM which supports EDID emulation? I know that there are all kinds of EDID-related complications for KVMs with DisplayPort, but it is not clear to me what will be sufficient requirements for HDMI-only KVM.