With two of the Category:Starting Weapons being Swords, Falchion may well be part of the path of Starting Weapons that the player chooses to Morph into Swords or advance along the Sword Progression.
Falchion is an important part of end-game or second-playthrough (New Game Plus) Sword Progressions also. Crossbow with Dagger has the only Morph to Falchion other than with high Tier Polearms: Siege Bow + Hatchet. All other combinations resulting in Falchion are devolutions of higher Tier Swords. This is important when crafting DAMASCUS swords, as Falchion can be used to combine with Shotels that drop in the Temple of Kiltia, and Damascus Polearms are rare.
In the second playthrough, with Godhands, there are no Rare Combinations with Sword as an ingredient, but there are a few with Sword as a product:
SILVER Great Sword + IRON Polearm, Silver Great Axe + HAGANE Crossbow, Silver Polearm + Hagane Dagger and Hagane Axe/Mace + Silver Polearm can all result in DAMASCUS Swords