Just a thought -- how might it have gone if fascist Germany (not necessarily Nazis specifically, depending on how far back the POD is) had primarily concentrated on regaining lost territory rather than pursuing a pan-Germanist agenda? In OTL, they let their former territory remain as part of Poland (West Prussia and Posen) while they annexed land which, pre-WW1, had belonged to somebody else (Austria & Czechoslovakia). If they had gone straight for Poland instead, would the other European powers have let it go in the same way they let Czechoslovakia go in OTL?