In Russia alone, “reviving the Soviet Union” would mean restoring socialism within its current borders rather than recreating the multi-national federation. That would take a political movement strong enough to win state power, nationalizing key industries and resources, reviving central economic planning, and re-establishing one-party socialist rule (or something close to it). In short: socialism in Russia first, then maybe expansion if others chose to join.
Also where are the Epstein files?