1. Each T5-d-R needs its own QNexus receiver for Canon wireless E-TTL integration. Canon 580EX or ST-E2 does the transmitting. QNexus allows you to just bring QF right into the existing Canon mix.
2. I believe for FreeWire to transmit Q-TTL you need Dw hot shoe adaptor.
I use Dw hotshoe adaptor when my single QFlash is on flash rotation bracket over camera.
When my QF is off camera, I started using QNexus with Canon wireless Master. As owner of a single QF, and working at closer in distances, I couldn't see going to FreeWire. My opinion is FreeWire is great for true wireless TTL, FEC, and Ratios over bigger distances, with 2-3-or more QFs.
I don't do weddings and stuff. I imagine for wedding work, or table groups, dances, the ability to remotely on-the-fly set Canon FEC (Q calls it AutoFill) and Ratios might be handy. I thnk if a person were, like just lighting up a high school gym or similar, would not not need QFlash at all, just mono or battery lights with a meter and/or trial and error. QFlash is too expensive for just making lights go pop.
I just need one good light and some fill. One good one does a lot.