For OKW I want to recommend you breakthru.
Panzerfussiliers are great unit that scales perfectly into lategame, outfight most allied infantry, his upgrade gives him 3xG43 and better recon and what is most important in 2v2, they are 6 member squad, thus less likely to get wiped.
Because OKW player has friend who can hold ground, he doesn´t have to 3 volks, 2x volks 2x sturmpios and 1x raketten should be enaugh, and once you get 2 VP´s get 2-3 panzerfussiliers use all your munnition to get G43.
In lategame you will get jagtiger that hardcounters any allied armor if well protected.
I much more like second OKW player that will go special OPS for commado panther. Commad panther can mark target (tank that is marked will get +50% DAMAGE).
Even strongst allied armor will die (marked)to shot from jagtiger and command panther, and if now, he can pursue them (panther).
Later on he can got kingtiger, there isn´t thing that can beat kingtiger+jagtiger + command panther.
Flares are cheap yet strong recon tool, infiltration grenades counter garrisons and infrared STG obers defeat any infantry(they ignore cover).
NOTE: Do not go officer from breaktrought, because if you lose him, whole army will retreat. Only use him if you can micro him behind your main army.
Breaktrought player should go battlegruppe with retreat point into fast panzer 4 (flak HQ), then jagtiger. This player can change
The other player want to rush flak HQ as well- to get infrared obers.
He should get leigts and 1 raketten, because he doesn´t have to spend manpower for pfuss spam.
He shouldn´t get armor, either tech for mechanized once he get flak HQ set up to rush kingtiger or save fuel for commado panther.
Commando panther and kingtiger are so expensive that you cannot allow to spend fuel on unwanted things. Get more rakettens if needed and make sure to not lose panzer 4 prematurely.
If you want to know how to set up HQs, read this guide.https://www.coh2.org/guides/34730/tip-of-the-week-9-okw-truck-placement
Ostheer is fine as faction, but this combo is much better, at least against UKF comet spam and USF riflemen spam - a really used strategy right now. If you face soviet player with maxim spam, invest more on leits.
Alsways hold your side to get tanks in time, tr to harass if possible.
So you would say its better to two OKW, then say 1x OKW and 1x Wehrmacht?