As the Netherlands, do not cave to the Germans, continue the Zuiderzee works, and do not lose control of any of your continental European states until 1945.
As Poland in the 1939 “Blitzkrieg” scenario start, inflict over 1,800,000 casualties to Germany to beat the 2018 PDXCON HOI4 challenge. Extra bragging rights if you do it in 30 minutes or less!
As any Allied Nation (in faction with a democratic Britain), enforce a peacedeal on Germany that disarms the Rhineland and makes it a demilitarized zone.