I've never tried it & don't know which sim it was originally intended for. If it's an FSDS2 or Gmax model for CFS2 or FS2002 it should work fine in FS9. The flight dynamics might need a tweak.
Ah, an FS9 model in FS2002 might be a tad different. Depends how old it is & if it was created with a proper FS9 model. If it's freeware I can only suggest you try it.