Out of interest, why is it you would suppose Russia is not an imperialist country? Perhaps because al it is really doing is seeking to hang onto and maintain its sphere of influence, not trying to aggressively expand it in the way the US seems to be doing?
They don’t exploit anyone. They have a cooperative or solidarity attitude towards their alliances similar to the Bolivarian Trade Bloc in Latin America. They don’t give orders. They don’t threaten countries that won’t obey. They don’t push austerity programs via the IMF. They don’t push free trade treaties with other countries that would wipe out that country’s industry so that Russian capital and corporations can come in and colonize the economy.
Russia is an ally of Venezuela, Cuba, Bolivia, Ecuador, Nicaragua, Vietnam, Laos, and China. All of those are openly socialist or Leftist countries more or less. No imperialist country would ever cooperate with socialist countries. They don’t do that. Imperialist countries try to destroy all socialist or even vaguely progressive countries. That is what imperialism is all about.
Russia doesn’t care what kind of economic system you have. You can have any sort of economic system you want from radical capitalism to heavy socialism and Russia will work with you. Imperialist countries always impose economic systems on their vassals, usually a neoliberal or radical capitalist model so that the imperialist country can exploit the vassal state by taking over its industries via investment and corporations, buying its raw materials exports for way too cheap and forcing the vassal to import expensive finished products from the imperialist state, after forcing out of business all of the local industries that engaged in import substitution.
Russia doesn’t menace, invade, conquer and colonize countries that did nothing at all to them. Russia does not impose sanctions on other countries. Russia doesn’t not go into other countries and steal billions of their dollars or confiscate all their gold reserves. Russia doesn’t throw its weight around like a bull in a china shop.