If we can find a mechanism to make it work (I'll leave that to others), then the Germans will have been bled dry, which means that Operation Barbarossa, assuming it even happens (unlikely but depressingly possible), will collapse at the Stalin Line.
Hard to have a result different from all or nothing.
And it will be necessary to find arguments for France resisting 6 months.
OTL, France fell because it had not enough reserves in troops and because its biggest army had been got around and cut from its supply line by a faster and leaner army that was able to inflict devastating shocks on a localized point.
So if you want France to hold longer than 6 weeks, I think your only option is fall gelb to fail. Which means Germany has no alternative plan and does not know how to fight a war Hitler thought would not happen in 1939/40.
Basically if fall gelb fails, it means the western allies will have time to bring their forces to a level where nazi Germany can no longer beat them.
Hitler's strategy was all about bluffing, poker and surprise through speed.