Stunning floor length dress

Floor length dress. Dark pewter silver/blue color. Lightweight velvet. US size 4 but material has stretch. Drapey cowl neck in front and strappy open back, has a slit on left leg. Bottom has narrow pleating. This dress is 68-69” long from shoulder to hem but could be easily hemmed. New with tags never worn from ASOS. LAST PIC (purple) is NOT this exact dress, but another one from ASOS with the same type of draped neck. I could not find the image for this exact style dress.