Flutter speech_to_text Locale Issue: Android Emulator Supports Japanese, But Pixel Defaults to English

I'm building a Flutter app that uses the https://pub.dev/packages/speech_to_text v6.6.2 package for speech-to-text functionality. My app works perfectly with Japanese (ja-JP) voice input on the Android emulator via VS Code. However, when I run the same app on my Google Pixel 8a (same Android 15 version), the speech recognition seems to default to English, even though I have installed all the Japanese language packs on the Pixel. Even when the locale is set to ja_JP on my Pixel, speaking in Japanese results in an English output, and is the same outcome when I try to set it to languages other than Japanese.

• Is this a locale issue at a deeper level than what my mobile settings can change?
• Is it perhaps something I can fix with my build settings, etc.?
• Why is ja_JP supported on the emulator but not on my Pixel?

Here is a snippet of the relevant parts of my code:

// speech_to_text
late SpeechToText _speechToText;
bool _speechEnabled = false;
bool _isMicRecording = false;
String? _voiceMessage = '';

@override
void initState() {
  super.initState();
  _speechToText = SpeechToText();
  _initSpeech();
}

// Initialize SpeechToText
void _initSpeech() async {
  _speechEnabled = await _speechToText.initialize();
  setState(() {});
}

// Start listening for speech
void _startListening() async {
  setState(() {
    _isMicRecording = true;
  });
  await _speechToText.listen(
    onResult: _onSpeechResult,
    listenFor: Duration(minutes: 1),
    pauseFor: Duration(minutes: 1),
    listenOptions: SpeechListenOptions(
      partialResults: true,
    ),
    localeId: 'ja_JP', // Where I set the locale
  );
}

What I've tried:

• Download Japanese language pack on Pixel
• Delete English, set JP as default language
• Tried my app with 2 other android devices, same result
• added ALL permissions I need in AndroidManifest.xml

What I've noticed:

• The emulator does not have Japanese installed in its system settings, yet it still recognizes Japanese speech without issues.

• Setting the Pixel's language to EN doesn't show ja_JP in its list of locales, but setting the Pixel to JP makes the locale appear. Either way, even though it says its set to ja_JP, the voice input is always English

  Any advice helps, thank you!