Don’t think too easily about this climb. Especially the last part of this climb has no moment of recovery. You have to fight this climb. You will have to push the pedals hard while slowly crawling up.
Hard to tell if you should include this climb in your route before you enter La Planche des Belles Filles or after. In the 6th stage of the 2019 Tour de France, the Col des Chevrères was climbed first and then finished at the top of the Planche des Belles Filles. This stage was won by the Belgian rider Dylan Teuns.
This climb is a real killer for the legs
The percentage at Col des Chevrères will increase up to 18%. The last kilometers of this climb even doesn’t go below 10%. So even with a 34×28 this climb is very tough. So think carefully about which cassette you want to take on in the Vosges especially when Col des Chevrères is part of your route.