Interesting although since they haven't fought over the Sudetenland (and basically losing all the fortifications/lines of defence etc), imo it's less likely they would do it now when they are totally exposed.
But IF somehow they do, makes one wonder what the french and UK do, still nothing or they actually declare war on Germany? There is no RM pact at this time, but anyway i doubt whatever assistance will make any difference, even if the soviets send significant quantities.
Of course, the germans WILL loose a portion of the tank, artillery, and production capacities that they got OTL, either destroyed in fighting or sabotaged etc.
Well, if somehow the UK and France do declare war in March-April, and probably still do nothing, the germans might forget about Poland and Danzig and attack France first (i'm sure there must be some TLs about just that scenario around) in summer/autumn. Of course, if the french/ UK are still as anemic and just sit there waiting for the germans to attack probably France is still occupied (probably they would be worse relative to the germans as far as military capability is concerned with a shorter drole the guerre, less production, hardly any US deliveries etc).