What kind of PODs are we looking at. And would it be possible for the Germans to reach the outskirts of Paris and stay there. If not that's fine. I just wanted to add some not so subtle symbolism.
Peferably have all of the things below:
King Carol I of Romania puts his foot down and has the country honor its secret obligations and join the CPs. Unpopular with the public, but will throw a big monkey wrench in the Russian mobilization plans, making their initial offensives vs Germany and A-H less efective.
The orders to Admiral Essen to turn back are delayed as a butterfly, and he gets into a fight with the Swedish navy in Gotland, bringing Sweden into the CP camp.
A-H and its commander, Conrad von Hotzendorf sticks to the initial plan of mobilizing in Galicia and even launch minor offensives against the not-yet-mobilized Russian units in the area. When the Russians finally attack, A-H is dug in and waiting. Galicia and the cream of the A-H army (including the all-important multilingual officer corps) isn't lost. The A-H now has a chance to expand far more effectively and be way more efficient as a fighting force.
The above leads to Serbia being the one to launch disastrous offensives against dug-in troops on hilltops, not the austrians, AND, Bulgaria isn't spooked by the Russian advance, meaning it joins the CP's right then in 1914.
This spells the end for Serbia, and a joint A-H - Bulgarian offensive (with some limited German support) in early 1915 should finish them off with little CP losses. If they're lucky, they might even cut off the Serbian army from escaping.
In the west, the French fith army is trapped and encirled (as nearly happened).
Battle of the frontiers goes as OTL (as a huge French defeat)
At the Marne, the Germans draw with the French instead of being pushed back, as they don't panick and send troops back east to contain the Russians. They then swing north-west and win the Race to the Sea. The BEF is deployed too far off east into Belgium, cut off and destroyed.
Antwerp's nitrate stocks are captured as OTL.
In Prussia, the Russian manage to lay siege to Konigsberg and outlying German fortresses, but suffer a huge defeat ala OTL Tannenberg once the Germans transfer forces from France.
The Goeben and Breslau still escape to Constantinople, and the Ottomans join the CP's.
Italy should by now realize that the CP's will win and don't enter the war. Greece however (with its pro-CP King and military) does after CP forces give the King the support needed to kick PM Venizelos out.
On the naval side:
In the Atlantic, Admiral Graf Spee and his squadron manages to ambush the British fleet in the Falklands (almost happened) and subsequently enjoys a lucky escape to Europe.
ATL Jutland is still a draw.
In spring 1915, after a failed offensive against Paris and the unsuccessfull battle of Jutland, Germany commits to a long-term war. They prioritize Russia while keeping a defensive posture in the west and start building (both in their and in neutral shipyards) merchant subs which they use to trade for critical materials with the Americans.
Russia finally gives up in the closing days of the 1917 winter after morale on its home front collapses following defeats in the field. German attempts to defeat France however fail in 1917 and 1918, due in part also to American backing and later entry into the war.
In 1919, the Allies regain the initiative but fail to break the German defensese. By 1920 however, with the Americans pouring more and more men, Italy finally joining and not enough grain coming in from the Ukraine, the Central Powers finally collapse.
Is two extra years of carnage enough ?