YES

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

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

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