I am not sure that there is an advantage in doing that, as the newest version of Sonobus now will recognize all of the channels on your interface and allow you to mix, eq, etc. within Sonobus, and adding S1 to the chain will increase latency. But that said, I am a longtime S1 user who, prior to the new multitrack version of Sonobus, used to route through S1 in order to use the 8 mics on my drums. My setup was:
1. Presonus Universal Control (if you are using a Presonus DI): Turn UC mixer off
2. If you are on a Mac, Install Blackhole 16 channel
(there is also a 2 channel version) routing software (free) https://existential.audio/blackhole/
If you are on a PC it gets dicier, you will need to use Jacktrip, but I can't help with that
3. Set up Studio One to create a second monitor (Song/Song Setup/Audio IO/Audio Output) and click the box for monitor (there is help for this in the S1 documentation and on YouTube)
4. In Studio One send the monitor output to Blackhole ch
5. In Sonobus set the input to Blackhole 16 ch and output to where you want to monitor from
Then any of the mixing, effects, etc. that you do in S1 will flow to Sonobus.
But again, it is so much simpler, lower latency, and easier, thanks to Jesse, to do all of your mixing, eq, compression, etc. right in Sonobus, and record the tracks. If you did not lay any effects on in Sonobus, you could then export the dry tracks from Sonobus and drop them into S1 if you wanted to do a better mix/effects there.
I don't know if that is what you were looking for, but I hope it helps.