Legendary Armaments Trophy in ELDEN RING

Nine legendary armaments count. Godslayer's Greatsword is also called legendary but is not one of them. One of the nine can be missed: the Bolt of Gransax in Leyndell, Royal Capital, is out of reach once you defeat Maliketh, the Black Blade, and the city turns to ash. Pick it up on your first visit. Kill Knight Bernahl, the merchant in knight's armour in the Warmaster's Shack in Stormhill, early for the Devourer's Scepter as well: he leaves the shack later in the game. The checklist has each one's place, and PowerPyx's location guide has screenshots of each location.