Even without unconditional surrender, the only thing the Allies would have gone for would have been removal of the governments, Nazi and Japanese militarists, disarmament, reparations. Once the Holocaust and the Japanese war crimes came to light, giving up the criminals would be part of the deal. FWIW when the Japanese made the vague overtures they did in the late summer of 1945, one of their conditions was they would try anyone of theirs accused of crimes. IMHO for either the Germans or Japanese to end the war on any terms the Allies would accept they would have to be really beaten down first, at which point why accept anything less than unconditional surrender.
Had the Valkyrie plotters taken over in 1941 or 1942 maybe, just maybe they could have ended the war with a return to status quo ante bellum in terms of borders (yes Anschluß, no Sudentenland) significant disarmament and reparations, as well as turning over the big Nazis to the Allies. By 1944 it was way too late - they were deceiving themselves that by removing the top Nazis they could mollify the Allies.
As several threads have discussed, if Stalin is killed or for some other reason the USSR throws in the sponge and the Nazis accept a Brest-Litovsk, you may end up with an end to the war like Calbear described. Until the Germans are losing so badly they can't see any way to win (except in Hitler's deranged mind), why would they quit when "winning". When they are on the ropes, they aren't aloud to quit. As far as Japan goes, the only way it ends before it did is if Hirohito decides to end it, and can do so without being taken in to "protective custody".