he best variation on the scenario is Germany does not invade Belgium, instead sending more Corp to the East, Britain cordons the Channel, Joffre sends the 5th through Belgian Luxembourg prompting the Third to attack through Belgium south of the Meuse, drawing more troops otherwise to be sent East, the French have a very bad opening and get flanked, suffering high losses but not as much territory, Russia takes losses and A-H does better. That could get you to end of 1915 and an armistice, likely end of 1916 and a cold peace. Italy sits it out, OE maybe gets hostile very late if at all. Japan is poised to shift toward Germany Britain is not a belligerent but did not abandon the Entente entirely. Germany is undefeated but not victorious, A-H survives, France is not defeated but humbled, Russia should still be a tottering mess.
Here Britain will support the "cold war" that settles in between France and Germany, try to intervene in Russia and ind its balance in China unraveling. Germany might gain some colonial scraps from France, like French Congo, or a piece of Chad, but no sweeping changes, instead remaining the third colonial power. Britain should see an imperial preference a good thing and try to snub Germany, but if they engage them then Germany will dial back as global trade was far more important than any bits and bobs on the continental map. The 1920s are tense, the 1930s are detente and by the 1940s things are rather back to usual. Germany will return as the second naval power but have little interest in upsetting the European dominance, the colonial system or global free trade. We might see some "ideological" divide but nothing as extreme as USSR versus USA, this will be a cool relationship but built on mutual commerce, more like PRC versus USA. If Russia falls to chaos then Germany is the bulwark, if Russia stays benign then Germany is viewed with more fear as it is the hound in pursuit of the British hegemon. I think the game shifts to China and jockeying to exploit it. The USA will condone the Americas and promote free trade, be jealous in China but otherwise a non-actor. Japan should shift more to the German camp. It might be rather more modern but very much the old Great Power games.