An airfoil like the well known Clark Y works best when moving forward and right side up, yet planes with this airfoil will fly inverted. I'm sure that it will also lift backwards and even inverted backwards. The shape is just not optimum in that configuration.
When I windsurfed a lot, I would sometimes jibe the board but not flip the sail, sailing off with the sail "clew first". This was mostly done on light wind days when you needed to do tricks to make it interesting. The ease with which windsurfers can be sailed backwards and the cluster-****s that this caused at the starting lines of races lead to the creation of a special sailing rule just for windsurfers. "A boat clear ahead no longer has the right of way if it is sailing backwards."