While this is a cool idea, for us to consider it seriously, you'd have to demonstrate how the two keypresses can be differentiated outside of AutoKey. IDK what the desktop environment and lower levels like drivers do, but I would expect them to emit identical scan codes. If that's the case, AutoKey would have no way of detecting the difference.

If you want to go down a rabbit hole, you can look into xmodmap and xkb. If they can tell the difference between the two keyboards, then you might be able to remap the keys on only the secondary keyboard to emit different characters that AutoKey could respond to. This approach has the advantage of being essentially independent of AutoKey, so you can ask the Linux gurus questions about it without even mentioning AutoKey which would be a lot more likely to get useful answers.

Another direction to pursue was suggested by Le Chat AI:

If I have two keyboards attached to a Linux system, is it possibe to tell which keyboard pressed a key in software like bash or Python?
Yes, it is possible to detect which keyboard pressed a key in a Linux system. You can use tools like evtest or xinput to monitor input events from specific keyboards.

Using evtest
evtest is a command-line utility that allows you to monitor input events from devices in the /dev/input/ directory. Here’s how you can use it:

Install evtest:

Copy
sudo apt-get install evtest
List input devices:

Copy
sudo evtest
This will display a list of input devices. Identify the device IDs of your keyboards.

Monitor a specific keyboard:

Copy
sudo evtest /dev/input/eventX
Replace eventX with the appropriate event number for your keyboard. This will show you the key events from that specific keyboard.

Using xinput
xinput is another tool that can be used to monitor input devices in an X session. Here’s how you can use it:

List input devices:

Copy
xinput list
This will display a list of input devices. Identify the IDs of your keyboards.

Monitor a specific keyboard:

Copy
xinput test ID
Replace ID with the appropriate ID for your keyboard. This will show you the key events from that specific keyboard.

Example
Here is an example of using xinput to monitor a specific keyboard:

Copy
xinput list
Output:

Copy
⎡ Virtual core pointer id=2 [master pointer (3)]
⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)]
⎜ ↳ bcm5974 id=13 [slave pointer (2)]
⎜ ↳ Logitech Unifying Device. Wireless PID:1028 id=9 [slave pointer (2)]
⎣ Virtual core keyboard id=3 [master keyboard (2)]
↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)]
↳ Power Button id=6 [slave keyboard (3)]
↳ Power Button id=7 [slave keyboard (3)]
↳ Sleep Button id=8 [slave keyboard (3)]
↳ FaceTime HD Camera (Built-in) id=11 [slave keyboard (3)]
↳ Apple Inc. Apple Internal Keyboard / Trackpad id=12 [slave keyboard (3)]
↳ daskeyboard id=10 [slave keyboard (3)]
↳ daskeyboard id=14 [slave keyboard (3)]
To monitor the daskeyboard with ID 14:

Copy
xinput test 14
This will output key events from the daskeyboard1.

By using these tools, you can programmatically determine which keyboard generated a key press event in your Linux system.

This sounds hopeful, but hopefully you won't need sudo after you figure out what's going on. Running sudo from inside AutoKey - even if you can figure out how to get it authorized securely, is probably not a good idea.

The Customized special keys entry in the wiki might be useful to check the output of each keyboard.