So why is the ECB lowering rates before the FED?
Europe and US are in different positions. They have different economic situations that allows one or the other to make decisions the way that they are doing now. Basically they have different problems to prioritize.
ECB is not that concerned about inflation but rather growth.
Is it because they are scared of a second wave of inflation?
Yes they are basically scared that by cutting rates there will a much long lasting impact of inflation. They are saying that they are waiting for a greater clarity before they make any decision that could have too much affect.