The instructions of the Onyx Shirt already give some information about the recommended fabrics to use, but let’s elaborate bit on that. The Onyx is designed for woven fabrics with no stretch. It works best made up in medium to lightweight fabrics, such as cotton voile, batiste, lawn, rayon/viscose, (double) gauze, silk blends, linen, quilting cottons, wax fabrics or poly blends. Basically anything woven without stretch that’s not too heavy! Even a chiffon would work, and could give it a very chique look.
When looking for a fabric, the main factor to keep in mind is the drape. The drape of the fabric will determine the silhouette of your shirt: a quilting cotton for instance doesn’t haven much drape and will make for a boxy garment. The cropped View B would look stunning in a wax cotton for instance. A rayon on the other hand has a lot of drape and will skim your figure. So even though the design of the Onyx is somewhat boxy of itself, the fabric you choose will exaggerate or diminish that effect.
When selecting a fabric with a lot of drape, you might want to choose not to sew the cuffs and epaulet. The cuffs need some stability to stay rolled up. When made up in a fabric with a lot of drape they might have the tendency to unfold, even when held up by the epaulet. You could interface the cuffs with a lightweight fusible if you want, but this could create a contrast with the drape of the sleeves. It’s all up to your preferences!