Nobody fucks up the ruling class of another country just like the US. You have to install a puppet at the helm of the newly "liberated" country. So the EU would first have to find Western loving people in Russia, fund the fuck out of them, bribe current officials, and get somebody close enough to Putin to "depose" him. It takes planning and would probably take more than a year, during which they still have to fund Ukraine.

I imagine massively investing in defense and helping out Ukraine will also be a long-term strategy to prevent the same thing happening in the future to the Baltics.