If there is a nick or flaw on the blade, it can, doesn't mean it will. If there is something unusual about the blade and it hits bone and leaves a mark, it can leave a tell tale sign. If the guard happened to be chipped or misshapen, and left a mark on the body it could be identifiable.
I can't say that the average ME would see or notice it, assuming such identifiers exist on the knife, but they could.
However, if it was a knife with serrations and those were used to "cut" ( more like saw), it's harder to see imperfections. Exception being if one of a set of serrations was damaged.
You
could have that one in a million everything lines up and X knife and only x knife could have done this, but it's usually something along the lines of "any knife of this size and shape missing a tip (as an example) could have been the murder weapon". If the suspect happens to have one of those, circumstantial evidence. If there is a blood match to a victim from blood wedged between the guard and the blade or handle, physical evidence. If by the powers that be a broken tip knife matches a tip found in a victim and the break matches perfectly, go buy a lottery ticket.
Jmo based on personal experience.