Europe is one of the biggest economical block, there is already a lot of soft power EU can exert via tariffs and bans.
Military is not as important as it used to be.
Russia is not going to attack EU country ever.
Who is going to buy their gas and oil?
They had to use the 'greenmen' to attack mainland Ukraine in attempt to reduce international backlash.
Europe invests 1%-2% in their military.
By comparison, Russia invests 5%-6%, but it's GDP is similar to Italy, i'd claim the "stick" ( if required) is a bit larger than you might expect :)
After all, it's mostly a numbers game.
If Europe wants to be taken seriously, it can't just be the French having a medium sized stick to back their soft power.