Russia attacks EU, US stay neutral, US stay neutral, China leverage on Russia being busy to invade Eastern Russia, the conflict spread to former colonies where Russia, China, France, UK are already in cold war. Meanwhile, Turkey finally attack Greece, and Iran takes the opportunity gain influence most likely with their spy network.

As usual, America stays neutral, until US get dragged in the war (Taiwan or Israel) while Argentina wait for the last day to formally declare war. Not sure whether Japan would invade China or take back the Sakhaline island

TL/DR : Russia/Turkey/Israel versus EU/China/Iran.

As you see I am absolutely not an expert