Ok My thoughts.
1 Eickhorn dagger ferruel has cast in lines whereas Alcoso are engraved.
2.Eickhorn spanner bolt usually found with pig latin number "Roman Numeral style" instead of convential number ( This info from Wittmann)
3.Wing tips much more upswept on Eickhorn.
4. Scabbard band holes sans protruding inserts where as Alcoso more like the scabbard pictured.
I personally DON'T like the spanner bolt screw driver slot instead of the two hole take down. This is only my opinion and am open to any other points of view.