It can’t. The MQA diagram mentions some sort of ‘side loaded’ DSP, which short of any further supporting info from MQA, we have to assume will need to be specifically written around MQA possibly via their API.
They’ve been pretty clear that just altering the bit-perfect data ad-hoc will make it non-MQA. DSP code will probably have to check-in with their internal integrity/security code.
The fact that al the data for this isn’t published makes me think they want to keep it under wraps outside of commercial interests, or they haven’t got all the pieces to the puzzle sorted out yet.
See here also https://community.roonlabs.com/t/mqa-and-room-correction/22634