Title says it all:

What weapons did you personally flat out have no use for? The Sky Render/Mutsunokami was the only katana I really used in the World of Ruin. Scimitar/Zantetsuken was just...better. Blood Sword and Soul Sabre weren't ever equipped. Sabin's Poison Claw served no purpose with the Fire Knuckles being viable until the World of Ruin. Never bothered with the Rainbow Brush or Angel's Brush either since the Magus Rod is light years better.