Hmm, actually alot of avrs don't have an optical output and neither does the shield. The hw700ds has hdmi, though if you're after 4k hdr you would need an avr with 2 hdmi outputs, one to the tv and one to the hw700ds as the hw700ds' base doesnt have hdmi 2.0 ports for 4k hdr passthrough. I'm pretty sure the avr can passthrough the audio to the hw700ds but not 100% so I'd recommend more research on that path to confirm.
Any builtin avr headphone surround I've tried though wasnt actual surround sound just crossfeed and reverb instead of hrtf convolution. I've tried denons, yamahas, and sonys.
Truly, the best and easiest headphone surround sound is through a pc, if you can make that happen.