Since this embellished Valentino gown is clearly the standout piece, I'd keep the accessories super neutral with nude Gianvito Rossi heels and a nude, textured clutch from Alaia. The vibe to me is that of a desert queen, something from Star Wars or Mad Max. The beauty look would involve a slightly undone top-not, matte face, and dark burgundy lipstick.
The aptly named Conqueror gown by Maticevski would be my second pick. It also has a slightly sci-fi feel to it. I love the minimalist, structural design paired with the deep plum color of the fabric. It softens the look and adds an element of warmth. I'd pair it with feminine, burgundy bow heels from Alexandre Birman and an embroidered Bottega Veneta clutch to add texture and a bit more color. The beauty look would be smooth, slicked back hair and a fresh, dewy face made with just BB cream, moisturizer, and lip balm.