It's not clear:
-if you have an audio interface for your computer
-why would you use 2 stereo mixers thru the Eventide….when it would be better to be placed in their SENDs/RETURNs, rather than in series.
A single stereo mixer could benefit from 2 stereo sends/returns to the H8000, using the 2 DSps in parallel for multiple fx on each channel…and avoiding noise owed to ground loops and multiple power feeds in the chain, as w/2 mixers. You'd also get to monitor the H8000, depending on the mixer bus configurations possibilities.
If you do not have an audio interface and want to record tracks thru the H8000 (as audio interface, then) AND then apply fx later, a single routing could give you 4 analog input for recording, going straight from analog input to firewire output, without using the DSPs. Then the FireWire connection could be used to create the S/Return connection on your DAW, depending on how it has the ability to be configured for this purpose. FW would feed DSPs A and B in parallel, as 2 independent stereo machines.
Probably factory routing #27 Analog & Firewire AB could do it as it is or with some mods, depending on how your DAW will handle I/Os and Sends/Returns.
all the best