Timras gave a very good answer. Just to simplify a few points:
-FinRus setup at CT is about the Continuation War (1941-44) which occures after Op Barbarossa... not about the Winter War (1939-40). There simply are no proper planes for Winter War. Lapland War setup could be there, but the real air action in Lapland War was quite limited.
-Finns fought 3 separate wars during WW2:
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Winter War against Russians, Nov 1939 - Mar 1940Germany was then allied with Russia and e.g. prevented Finland from getting Fiat fighters from Italy through their railroads. Many allied countries sympathized with Finland and tried to help.
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Continuation War against Russians, Jun 1941 - Sep 1944Finland allowed Germans to use their territory and joined in fighting agains the Russians after Russians had "technically" made the first aggressions. Finns wanted to gain back the areas lost in Winter War, but also went in deeper to gain better positions for defence. Then the rest was upto how German and Russia would finish their fight. England declared war to Finland after Finns crossed the old 1939 borders, USA never did.
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Lapland War against Germans, Sep 1944 - Apr 1945At first a fake war... Germans retreated and Finns came after them attacking empty positions. Russia demanded real action and faster schedule to empty Germans from Finland and eventually it became a real war. Finns did not fight the Germans together with Russians, russians used some of the northern most areas of Finland in their attacks, but mainly Finns reclaimed Lapland themselves. Germans wanted to evade after all. Lots of bitterness on both sides, I guess, because of "betrayal of comradeship-in-arms" on one side and scorched earth tactics on the other side.
Finally, Yes, I think it is fair and perfectly ok to call Finns
Axis during 1941-44, or at least fighting on the Axis' side. "Allies" or "Axis" dont really include any feelings of good and bad to me