Russia is not fascist
the role tsarist russia played was of imperial nature because it still had enough “old world power” with its army, huge land and colonial periphery
genocidal proxy war
They want to do to Russia, what they have done to their colonies.
Russia is currently engaging in a fight for their own survival just like Iran
i am not even sure if Russia actually wants part of the imperial cake
The “marxist perspective” is definitely not something that would conclude Russia is imperialist.
But I would be looking for things like coercive relationships where the capital of Nation A is growing as a result of exploiting the land/labor/resources of Nation B.