Reaching through will be key. If you can get the vines to leaf out mostly on the top of the arch and keep the harvesting windows clear this should work out pretty great!

What if the whole raised bed was inside, and you run the trellis from the outside of a bed to the outside of the other bed? This would be good for shady plants, and you could do the opposite for sunny plants, which would definitely cut down the unused space overall, though maybe not 100%.