I came across this design a while back on the Internet, but I (as of lately) can't find the source (so forgive me if I can't credit the original creator).
From an alternate history perspective, this design was a compromise between the Russian majority and the growing Karelo-Finnish dominance. The tricolor is based on the flag of the old Karelo-Finnish SSR (which would be adopted OTL), but with the addition of a Nordic Cross design to represent the Nordic heritage of the republic. The flag ratio is 3:5 (roughly similar to that of Finland's flag). The blue cross is slightly smaller than OTL's flag of Karelia. This is based on the original design of the KFSSR and is to help give a clearer view of the cross. The vertical bar of the cross is located 1/3 towards the flag's hoist.
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