Just as the title poses. I know land fighting and deployment during the great war was already mechanized to a large extent. The main components (vehicles, armor, aircraft, artillery, horses 
) were already there. I find it hard to hard to define blitzkrieg besides a logistic nightmare, massing tanks, punching through enemy lines and advancing with mechanized speed, allowing one to flank and encircle. Maybe others have a better definition.
Genghis Khan did it 800 years ago, but massed cavalry attacks would have been destroyed by machine guns and artillery. Blitzkrieg depends on surprise as well as speed and the Germans tried it in 1914 but once the trains stopped the soldiers had to walk, giving France and the BEF a chance to recover and stop them. Both the French and the British tried it in 1917 when they had enough tanks (nobody had any in 1914), but the tactics were still being invented and the tanks were vulnerable to artillery fire and, frankly, to having been built by the French and British automobile industries. 
The attempts to use tanks in WWI were not exactly “blitzkreig” in the sense the term was used in WWII.
Blitzkrieg was not possible in World War I. There is a strange propensity for believe to believe tha the generals of WWI wanted static trench warfare to happen. They certainly did not; they liked maneuvre warfare. It was not possible on the Western front for 3+ years because the technology simply didn’t exist to overcome the ability of both sides to present a nearly impenetrable defence. In addition to the lack of armor, you also had a lack of easily portable wireless communication, which effectively meant that coordinaing offensive maneuvres for long than six hours or so was impossible; on the few occasions breakthroughs were made there wasn’t anything you do could about it because you couldn’t call in effective artillery support as needed on the fly, or call for help from other units. The lack of radios was as decisive as the lank of tanks.
They actually sort of did. Late in the war, the Germans worked out a rapid infantry assault tactic, bypassing strongpoints, and rushing like crazy for rear areas, which were less defended. It was nearly as effective as tanks were!
The. British tactics during the 100 Days campign was the precursor of Blitzkrieg. Attack on a narrow front with massed tanks supported by infantry, bypassing strong points.