The "VALLERYSTHAL" brand is present on the bottom of the cup.
This is a model published in the Masterbuch catalogue, Vallérysthal 1907, plate 226, Assiettes rebrûlées, model no. 3615.
For more detailed photos of this set, you can check out: https://www.dropbox.com/scl/fo/98xine11xxcry943wjupj/AGyUDAVahFQxeSdxPvvh6lQ?rlkey=dpx3mwes1ws4qaol8d3te9zos&st=6clf5ll8&dl=0