The biggest problem with multiple separate algorithms is how to handle the panning. But if you can drive the panning from your DAW into a multichannel bus, you can pretty easily use multiple instances of even stereo effects for immersive. There are mix engineers, for example, that use 3 or 4 hardware reverbs as a single 5.1 or 7.1 reverb (though most throw away the .1 signal or use it as a mono height send). Seems common to use the L/R pair of each unit as a front-to-back pair on the same side – that way any crosstalk between the channels doesn’t drift the signal left to right. But you could keep it simple with LR pairs directly matching the corresponding pairs of the mix bus. Same concept extends to the height speakers if you want those for reverb returns in any combination of LR or front to back.
This method would work just as well with stereo or multichannel H9000 effects or any other software/DAW hosted effect. All comes down to the panning/routing for the sends and how the returns map back to the mix bed or objects.
