MELD.

MELD gives an Atmos mix the bus processing that objects otherwise rule out. Every instance can see the others, so channels placed in one of 26 virtual groups share the same processor settings while each stays discrete for the renderer; a shared sidechain lets the group compress as one. It is modelled on how John Hanes of MixStar Studios matches immersive mixes to their stereo masters, and it works on stereo sessions too. It needs an iLok account; one licence covers macOS and Windows with two activations, and a dongle is optional.