Ooh that is beautiful!
I would probably go with ballet flats in a metallic silver or gold. Alternatively, a mary jane flat or small heel.
I know they aren't the most fashionable brand, but Hotter sell pumps and small heels which are really comfortable and look lovely.
E.g.
https://www.hotter.com/violet-shoes-beige-3009
https://www.hotter.com/duet-heels-metallic-3232
I have some of the flats which I was given. I would never have thought of going into Hotter for party shoes, but they're now my favourite with a LBD