The Broad-bodied Chaser is one of the most common dragonflies in Europe and central Asia.
It is very distinctive with a very broad flattened abdomen and both fore and hind wings have a dark patch at the base.
Males are blue; females are yellow.

1st photo: A female. In my yard, Hilversum, The Netherlands, 1 June 2016
2nd & 3rd photo: A female. Bargerveen, Emmen, The Netherlands, 15 May 2018
4th & 5th photo: A young male. De Groote Peel National Park, The Netherlands, 11 July 2018