Android - How to put a shortcut to a settings submenu on a home screen

Yes, it's possible to add a shortcut to a settings menu, but probably not as "deep" as you'd like.

Long-press on a screen and select "Shortcut" in the menu that pops up. Then choose "Settings" and then the settings menu you want.

You could use Manual Intent Shortcuts.
It offers to add a custom launcher widget that sends intents defined by you.

To launch the VoiceSearch Settings window, do the following:

• add a new "manual intents shortcut" widget to your home screen
• enter a name
• Action = "android.intent.action.MAIN"
• Component Package = "com.google.android.voicesearch"
• Component Class (FQDN) = "com.google.android.voicesearch.VoiceSearchPreferences"

Leave all other fields empty, uncheck "broadcast"

You now have a shortcut to the settings window you want.

PS: I used apktool to inspect the AndroidManifest.xml in VoiceSearch.apk (system app, you need root to access it) which lists this Activity.