The Bilen and Beja are genetically identical to the Tigre and Tigrinya. There's no difference between them besides language.
The Afar are a bit weird and do have deviant origins from the Habesha.

The Bilen and Beja are genetically identical to the Tigre and Tigrinya. There's no difference between them besides language.
The Afar are a bit weird and do have deviant origins from the Habesha.
So it's actually very easy to identify a Somali genetically from that group.