There are several PODs for this, or one continous thread leading up to it,I don't believe that it's plausible but let's get past that. But WI instead of the German fleet being scuttled and the Germans being allocated 3 10,000 coast defence battleships etc they were invited to Washington and given a naval allocation identical to France and Italy and the rest of the fleet scrapped? This would give Germany 5 of its most modern captial ships, the chance to build 5 Washington cruisers and 45,000t of carriers etc, etc, etc.
I doubt this would change much of the rest of the history of this period, a few things I can think of are; no pocket battleships, experience with better propulsion and weapons and a chance to work out their carriers (this would require its own POD of course). How would the German navy look in WW2 if rearming from this base? How would WW2 progress?