YES

   1: -(+(x1,x2)) -> +(-(x1),-(x2))
   2: +(-(x1),-(x2)) -> -(+(x1,x2))

@Rule Labeling
--- R
   1: -(+(x1,x2)) -> +(-(x1),-(x2))
   2: +(-(x1),-(x2)) -> -(+(x1,x2))

--- S
   1: -(+(x1,x2)) -> +(-(x1),-(x2))
   2: +(-(x1),-(x2)) -> -(+(x1,x2))