Its interesting, cause Russia used same tactic against Austria-Hungary century ago as they now using vs EU. Basically back then they funded and used so called "Pan-Slavism" movement (Russia as leader and savior of all Slavic people) where they funded separatist organizations inside A-H Empire and tried to sow internal discord, classic "divide and conquer".This is in Russia's playbook.
Same playbook now, but i guess thats the weakness of the multi-national states/organizations to be exploited.