It will not be wrong to say that World War I was a mix of new and old. The weapons were unique to the core and a range of Melee weapons was also used in the war. Below we list some of these so as to make you understand the dilemma of the situation.
This was one of the weapons which cannot be considered to be a truly improvised weapon and was not uniquely created for trench warfare. Kukri was used in the war and can essentially be considered to be a very long knife. Kukri has a concave kink and has the finish of a sharp point.
This was one of the most varied weapons used in World War I. This could also look alike to a stick of wood but when a hole for lead weight was drilled with the end being wrapped in a wire, it did become truly lethal.
This was not considered to be the most effective weapon but was the cheapest and the easiest one available during the war. French Nails was made from steel or bayonets. Its blades were brittle to the core and two to three French nails could be made out of a single bayonet.