France will be extra careful when it comes to keeping Germany down. Heck, a Communist takeover in Germany is quite likely to trigger French intervention in the first place. Paris and London tried to safe Tsarist Russia, they'd definitely attempt it in nearby Germany. But if, if the revolution in Germany goes through...
Germany has enough industry to stay economically powerful without the need for massive modernization measures. Agriculture also shouldn't be a problem. So I'd expect Communist/Spartacist Germany to be richer per capita than OTL's Soviet Union. Maybe Berlin tries to expand their sphere of influence, establishing close ties with the Communist parties in its new neighbors? Annexation with regional autonomy is a possibility as well.
For Russia it really depends on their territorial extent and the political system used (continuing Romanov dynasty or republicanism?). If enough regions went independent, maybe revanchism gets popular, leading to Russia becoming the first *fascist nation. Russia would definitely try to meddle in Asia and the new states that emerged post-WW1, however. Most of those nations were either Slavic and/or formerly Russian, so they have lots of reasons for it.