How to return data from a fragment using androidx.navigation?

In one parent activity.. just use global variable that able to access inside same parent activity or

Other trick you can try preference, so that preference will able to read anywhere you want.

Data share active fragment

sharedPref =  context.getSharedPreferences(context.getPackageName(),MODE_PRIVATE);
SharedPreferences.Editor prefEditor = sharedPref.edit();
prefEditor.putString(sKey, sValue);
prefEditor.apply();

Data read from other fragment

sharedPref =  context.getSharedPreferences(context.getPackageName(),MODE_PRIVATE);
sValue = sharedPref.getString(sKey,defValue);