1) If two people are on a phone call, and they want to pray a mustahab prayer, can one put a wireless earphone in an ear, and pray? Does it invalidate the prayer?

2) If I’m praying and I have an earphone in my right ear, and the other person is praying too, so I’ll hear like Quran and the things said in prayer, this invalidates it too?

1) Speaking during the prayer will invalidate it

2) Yes