Iron Dual Sword --> Twin Dagger --> Twin Dagger+ --> Hurricane --> Hurricane+ --> Double Dragon --> Dual Dragon Ultimus --> Blue Ogre Sword(Sword & Shield).
That is wrong.
Dual Dragon Ultimus only upgrades into Ultimus Heaven and Earth. Flaming Pair can be upgraded into Blue Ogre Sword. To make it from scratch you need Azure Lao Horns, and other materials that I cannot remember.