Make the Rune Song able to be forged into different weapon types

Make the Rune Song, which is THE legendary melee weapon, able to take the form of other weapon types which are all equally useful, but more/less fun depending on play style. For example, if I like to play with axes or spears over swords, make a “Symphonus Spear Mold” or something that can let me change the Rune Song into a spear. Even a “ Chakram of the Choir” mold would be awesome. It would add more variety/use to the Rune Song, and make it feel more worth while to get outside of just the achievement.