Holy sword of the Order

Looks like a broader two-handed longsword with a gold/jeweled/ornate hilt. This sword can be found on on the body of Patrick de Weyze after a battle during one path of an Chapter III sidequest. It can also be found on the body of Siegfried after you kill him in the streets of the Temple Quarter in the Epilogue. Can also be found in barracks near order smith. Also it can be found in the wardrobe in Siegfried's quarters.

Heiliges Schwert des Ordens Holy sword of the Order Glaive sacré de l'Ordre Spada sacra dell'Ordine Święcony miecz Zakonu