Method at a binaural hearing device system and a binaural hearing device system

A method performed by a binaural hearing device system, the system comprising (1) a first hearing device for placement at, or in, a first ear of a user, the first hearing device comprising a first input transducer arrangement, a first signal processor, and a first wireless communication interface, and (2) a second hearing device for placement at, or in, a second ear of the user, the second hearing device comprising a second input transducer arrangement, a second signal processor, and a second wireless communication interface, the method comprising:

• generating a first monaural beamforming signal by the first signal processor based on one or more input transducer signals provided by the first input transducer arrangement;
• obtaining a second monaural beamforming signal provided by the second hearing device;
• and
• determining a first bilateral beamforming signal based on the first and second monaural beamforming signals, wherein the first bilateral beamforming signal is determined based on a variable length finite impulse response (FIR) filter, the FIR filter having a filter length;
• wherein the first bilateral beamforming signal is based on α*l+β*r, wherein l is one of the first and second monaural beamforming signals, r is the other one of the first and second monaural beamforming signals, * represents a convolution operation, and α and β relate to the variable length FIR filter.