Generally the ones in western clothes is portuguese speaking. Angola was colonised and missionerised since the 1500's.
The Himba are nomads that never allowed themselves to be influenced and to this day they have strict rules regarding culture. They only speak Herero.
The girl in the pink pants however is Herero and is actually from Namibia, she has spent some time in Opuwo, a frontier like town in Kaokoland. She was just visiting. You will notice that like the Himba, she also had the bottom front teeth removed for cosmetic reasons.