Werneck was present at Aldenhoven on 1 March 1793 where Henri Christian Michel de Stengel's column was defeated by two Austrian cavalry regiments. He fought in the Battle of Neerwinden on 18 March. He served at the successful Siege of Valenciennes from 25 May to 27 July and at the failed Siege of Dunkirk from 24 August to 8 September. He led a brigade in József Alvinczi's Reserve at the Battle of Le Cateau on 29 March 1794. Promoted to Feldmarschall-Leutnant on 28 May, he served in the army of William, Hereditary Prince of Orange. In 1795 he led troops in François Sébastien de Croix de Clerfayt's army on the middle Rhine. The actions included the Battle of Mainz on 29 October, where he led the Reserve, and the Battle of Pfeddersheim on 10 November.