I can verify that when I removed the Share plugin these two permissions was no longer required:
android.permission.READ_EXTERNAL_STORAGE
android.permission.WRITE_EXTERNAL_STORAGE
I guess this is since the plugin can be used to share photos? Nepeo
But for me in my project I really just wanted to "share" a link to someone on whatsup/messanger, but since the app then requires permissions to read and write to your sd card then I think I will remove the share button now.. :)