There are $550 billion in frozen russian assets that could have been used if there was political will.
If needed, more could have been seized from russian oligarchs and citizens (e.g. ones who have openly showed support for genocidal imperialism - extremely common even among those in Europe).
There are also other methods like interment of executives/operatives who have been collaborating with the russians; this would not impact the average European or their lifestyle. If anything this would benefit the average citizen by lowering corruption and crime.
Look, I am not saying any of this is easy. I am just pointing out that it is possible to implement such measures and this is not a matter of "fairy tale thinking". It is possible, viable and has the opportunity to be very effective, the primary issue is the lack of leadership and courage. Everything else is largely an excuse.
So what is the EU going to do about this?