Via Dillard's. This technically sleeveless dress hits below the knee (on everyone except really tall models) and offers a high neckline, making it perfect for more business-formal offices. Pair it with a cardigan or jacket if you need to cover your arms a bit more. It is available in the pictured espresso "sharkskin" fabric made from polyester and rayon. The dress is $119; find it here.
The dress is part of Alex Marie's "Orchard Hill" collection made exclusively for Dillard's. Alex Marie also makes some other work-appropriate vegan dresses for Dillard's: (1) the "Diane" dress (I would check as to whether the accompanying belt is made from faux patent leather) -- $119; (2) the "Andrie" dress (more appropriate for less formal offices) -- $99; and (3) the "Adrianna" dress (on sale, select sizes remain) -- $41.70.