Interested to see how you get on with this.
I looked again at the fantastic CR tutorial to see if Studio Sends were a valid solution to setting up A/B referencing… turned out to be a bit convoluted for my brain. I’m sure it could work out, but not something I fancy repeating as standard workflow.
How about direct routing? Using the dropdown to redirect the entire path to another FX path (choose between inputA and inputB). So the original audio channel is blank. It has 2-3 options of output busses to toggle between. Output busses having their own FX paths.