There will always be some latency. USB usually has the highest amount of latency due to it’s software architecture. Using the Dante or Waves protocols will also have some latency, but generally less than using USB. If this is for a stream or broadcast, then the total latency doesn’t really matter (as long as it is accounted for and the audio and video synced together). However in a live setting, anything with a latency more than about 15ms is going to start being noticeable.
I think you will find that using USB to route audio out of and back into the console to add effects with some sort of DAW will usually result in too long of a delay to work in a live setting. Also keep in mind that not only have the latency from sending the audio to and from the computer, but each plugin may have it’s own latency as well. You really need to pay attention to the total latency and likely won’t be able to use anything but plugins that have zero or near zero latency when transmitting over USB.
.
.
