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I'm guessing you want decent coverage? In which case things like Clematis or Passionflower while providing beautiful flowers probably won't give you the foliage you want.
I agree with Brommers on the rose. Find something you like from David Austin https://www.davidaustinroses.co.uk/
Cheap roses are a false economy. Call them for advice if you need more help. Also roses keep their leaves until quite late and start them again early.You could also try something like a Star Jasmine as it's evergreen. But it will probably need a different planter, and if you do definitely buy an established one from a decent nursery.
I will be making planters for either side of this pergola I built today. What's a good climber to train up and over? West facing so lots of afternoon/evening sun, but not planted in the ground.