No more Italian offensives and no Kerensky offensive would be massive butterflies and save A-H. The latter basically initiated the death kneel of the Habsburgs, who even if on the winning side would probably fall post-war. if Russian and then Italy bow out of the war it saves the British more shipping, but means A-H can effectively demobilize and rehabilitate itself, while serving as a resources farm to some degree for Germany. Bulgaria too could effectively demobilize and save themselves if the Entente evacuates Salonika. Not good for the Entente even if they could keep fighting to some degree, but without US steel the French can't produce artillery, tanks, and shells in any sort of quantity. Britain can be hand to mouth, but France is effectively out of the war without shells. Plus if Russia drops out early and Germany has no need to send troops to Italy and France can't attack for the rest of the war except for limited counterattacks, then Britain can't launch Passchenadele, France doesn't launch their successful late 1917 offensive against the Chemin des Dames, and Germany attacks hard in 1917 in the west against a quite weak Entente with a stronger offensive than even in 1918 due to having more men and being less worn down from the fighting on all fronts in 1917.
I would imagine France if faced with a future inability to fight as per wikings comment above, along with Russia in an no American money scenario, will before the $ runs out, ask the USA or the Pope or the Dutch to negotiate a peace. Likely the Germans don't know the true extent of Allied weakness, and are worried about their own problems. In which case a compromise peace is possible, probably slightly Central Powers favorable, with the Germans taking Belgian and Portuguese colonial possessions (and maybe Liege or Luxemborg if the Germans are confident and press things), and Austria ends up with defacto control over Serbia (well worth it for the Germans+Austrians and politically acceptable enough for their Monarchies to survive).
The interesting part about such a peace conference is how much the main players would be willing to sell out their Allies for their own benefit.
Would France(+Britain) be willing to give the Belgian Congo AND/OR Portuguese Angola to get Northern France and Belgium liberated? (I would think so)
Would Russia be willing to give Austria defacto control over Serbia and Bulgaria, in exchange for getting territory back? (I would think so)
Would Germany be willing to give up their puppet government in Poland for peace? (I would think so).
Would German be willing to trade stuff to get the Ottomans Baghdad+the Hejaz back? (I would think not)
Would France+Britain be willing to give up Russian territory to get French territory back? (One would think, but the French will still need Russia in some form as an Ally)
With most of the German colonies in hand and some of the Ottoman empire, how much is Britain willing to give back to liberate French and Russian lands?
Even if Britain is willing to give back colonies is Japan, South Africa, Australia and New Zealand going to give up the colonies in their possession?