I can disable the software keyboard on an MC92N0 manually using:
Settings > Language & input > Keyboard & input method > Enable Hardware (Physical keyboard)
This stops the software keyboard coming up automatically when an input field has the focus.
Can I do this with StageNow? I know I can set the language but I do not see an option to enable the hardware keyboard and disable the software keyboard.
Unfortunately, that feature isn't available in StageNow. However, you could potentially use the Null Keyboard app to replace the default keyboard. This could help achieve the results you're looking for. Since the MC92N0 device doesn't have google play services, you can download the app from https://apkpure.com/null-keyboard/com.wparam.nullkeyboard