That's correct. There are two elements to any criminal offence, the mens rea and the actus reus. The mens rea in this case would be the purpose of manufacturing. Just having simple possession of a schematic, a drawing, etc. on your computer.... The intent is not to capture that by this offence. You would have to have that additional mens rea or the intent for the purpose of trafficking for the first offence.
As for the second offence, which would be the distribution of blueprints, you would have to have a mens rea of knowing that the blueprint, design or schematic would be used for the purpose of firearms trafficking, and it would have to be a firearm derived from the data.