Okay, it in 1941, and Hitler has just invaded the Soviet Union. For a few days, Stalin, at his isolated dacha, is basically in a fugue state, very out of it. But he bounces back, and takes command.
What if...instead of the history we know, during this period of vulnerability, those around him, in view of the massive casualties and retreat of the Red Army, move to remove Stalin. He is liquidated, and the new leaders sue for peace with Germany, offer them huge territorial concessions, whatever. Just stop.
Whither history?
What happens next would depend muchly on the value set to the undefined variable in your scenario: "the new leaders".
Who would those be?
The nature of the Soviet system, at least at that stage in its history, was rather "there can be only one!" in terms of leadership.
I don't think they'd really be willing to cede all of Soviet territory west of the Urals, which IIRC was the German war aim. But with no undisputed leader, they will be in a mess.
So let's play along with this - okay, so the Soviet Union is out for the count. Germany now has all the farmland they want, vast mineral resources, no shortage of oil, loads and loads of slave labor (what, you thought the Nazis were coming to
liberate you?) etc etc
If the UK and the USA do not make peace - well, it will be a long war, with Germany ruling the Eurasian landmass, and the Anglosphere ruling the oceans.
Then Imperial Japan starts doing its thing - well they were already in China and Korea, and maybe the leftover bits of the Soviet Union look tempting...
Theoretically, this could go towards some thing like Orwell's scenario of 3 mega-power nations all endlessly at war with each other.
The USA would probably still be the one to get the Atomic Bomb first, and fleets of long-range bomber planes. But Germany will be the first to have ballistic missiles.
Whether either of those would win the war without boots on the ground is a different question.