No ,it does nothing for a stamp in that condition . The edges are cut into plus it looks like a major cut/crease into the stamp .It would sell for $5.00 to $10.00 and no premium for inverted watermark .
On any stamp that old deciding between colors, and especially between shades of color, is hard enough when you have the stamp in front of you in daylight. Often it's impossible unless you have several copies for comparison. And from a scan? Can't be done with any degree of confidence.