Nephi separated his mention of the sword of Laban from the other artifacts because he uses it for an introduction to their need for defense. Regardless of how far away they had traveled, they had not escaped everyone who might wish them harm. The new community had to defend itself. Nephi declares that it is from the Lamanites, but it is the Lamanites in their function as the generic ancestral enemy. The actual threat might have been more likely for other populations who had no genetic relationship to Laman, Lemuel, or the sons of Ishmael.
When Nephi says that he makes swords after the manner of the sword of Laban, we find one of the early possible anachronisms in the text. There is no evidence of the required metallurgy in Mesoamerica during Book of Mormon times.
The first issue is what “after the manner” might mean. It cannot mean replicas, because Laban’s sword had a hilt of gold and was thus ceremonial. The weapons made for war would be more pragmatic. Thus, “after the manner” never meant a precise copy, but something similar.
The second issue is the type of metal used. We simply do not know and cannot reconstruct what it was. Iron ore was known, but the more commonly mentioned metals of gold, silver, and copper would not have made strong weapons. Regardless of what these initial swords might have been, they did not become the sword that was used in Mesoamerican warfare. Those swords were a wooden shaft into which obsidian blades were set. That weapon could be more easily built, and the obsidian blades were much sharper than the metal swords. It was also a more common technology to use obsidian.
Thus, whatever Nephi made, whatever those swords were, they did not alter the basic military technology. It is probable that soon after Nephi mentioned making these swords, they fell into disuse. Not only is it probable that the obsidian blades were a better technology at the time, but the method of using the swords differed. Thus, Nephi’s swords required not only a new construction technology, but the development of new ways to fight. The only thing that can be said for sure is that Nephi’s swords “after the manner [of Laban’s]” didn’t last.