The best fabrics for a sleeveless A-line dress are stable wovens for structure (poplin, twill, jacquard) and soft wovens for movement (crepe, viscose, challis)
If the dress code specifies black tie optional or formal, you have two excellent options to choose from, each with its own advantages and appropriate execution: The first and preferred option is a classic tuxedo well-fitted in black or midnight blue, both equally appropriate matched with a crisp white dress shirt with proper collar construction, a hand-tied black bow tie, and highly polished patent leather or calfskin dress shoes
For the Hopeless Romantic Its fitting that the Frederique gown should resonate with lovers of Old World romance because that crochet lace, those petite bows and that high neckline just scream vintage beauty
For guys, my top tip for putting together your engagement outfit is to try to avoid sneakers you can still opt for a comfortable shoe, but choose one with less of a workout vibe to it