Author here, the lantern is named after a region in golorian known as the ghostlight marsh. The lantern has nothing to do with seeing invisible or ethereal creatures, the game already had that in the lantern of revealing. Similar names, but that's about it.
Would have been very similar cause my initial idea thought seeing invisible would be cool. I scrapped that when I saw the lantern of revealing. Cool superstar item though ( went back and looked!)