ref: https://stackoverflow.com/questions/38010494/is-it-possible-to-toggle-software-keyboard-via-the-code-in-ui-test/38036149

turn_off_ ConnectHardwareKeyboard.js

const exec = require("child_process").execSync;

const devicePreferences = exec(
  `/usr/libexec/PlistBuddy -c "Print :DevicePreferences" ~/Library/Preferences/com.apple.iphonesimulator.plist`
).toString();
const regexp = /\s+([A-Za-z0-9-]+)\s=\sDict\s\{/g;
let matched = [];
while ((matched = regexp.exec(devicePreferences)) !== null) {
  const simulatorUuid = matched[1];
  try {
    exec(
      `/usr/libexec/PlistBuddy -c "Set :DevicePreferences:${simulatorUuid}:ConnectHardwareKeyboard false" ~/Library/Preferences/com.apple.iphonesimulator.plist`
    );
  } catch (error) {
    exec(
      `/usr/libexec/PlistBuddy -c  "Add :DevicePreferences:${simulatorUuid}:ConnectHardwareKeyboard bool false" ~/Library/Preferences/com.apple.iphonesimulator.plist`
    );
  }
}

tell application "Simulator"
    activate
end tell

tell application "System Events"
    set hwKB to value of attribute "AXMenuItemMarkChar" of menu item "Connect Hardware Keyboard" of menu 1 of menu item "Keyboard" of menu 1 of menu bar item "Hardware" of menu bar 1 of application process "Simulator"
    if ((hwKB as string) is equal to "missing value") then
      do shell script "echo 'hardware keyboard is off'"
    else
      click menu item "Connect Hardware Keyboard" of menu 1 of menu item "Keyboard" of menu 1 of menu bar item "Hardware" of menu bar 1 of application process "Simulator"
    end if
end tell