Taking Russia is almost impossible for Germany to do w/o taking any Ipc’s away. I would buy men first b/c it takes them longer to get to Russia and you need a ton of fodder for your tanks and planes to be effective. Russia will probably buy a ftr, and 4 men on the first turn. It will be able to spend 29 on the t2 if russia takes the ukraine and west russia back. So expect Russia to load up men, and they should have plenty of men by the time you can actually muster up a force.
I would switch my plan to the uk w/ bombers and reseach for rockets. It’s easier to take land away from the uk with hardly any forces at all in Africa. If you build a AC and a Transport on the first turn you have a better navy than \what the uk has to offer.
Once you deplete the uk of money Germany and japan will be able to work as team to conquer Russia.