Rosa 'Korbin' syn. Rosa 'Iceberg', Rosa 'Fee des Neiges', Rosa 'Schneewittchen'

Should I plant one either side of the arch or put jasmine the other and let them intertwine and grow through each other? Would this even work?

I find that any climber with good pliable stems is good growing through trellis, and adds interest to have different plants. I've got a honeysuckle and trumpet vine growing up a tree together 👌🏼

Thanks @richard.spicer.7906 ! The plan could work then, just have to debate if my ocd could cope with the unevenness for a few years?

You could try both? (If that's an option) - plant a rose each side but then also plant something that will also grow through the Rose? The roses will have leaves and flowers during the summer, so maybe find a climber that has a different seasonal interest and perhaps something with small leaves and flowers that wouldn't completely block out the Rose - essentially anything that flowers between late autumn and Spring?