Milo,
this is
Omalus biaccinctus.
As you wrote, it's the only one in Central Europe with this colour pattern.
Omalus aeneus and
O. puncticollis are green to blue, sometimes even violet, however never bicoloured as your specimens.
The mesoscutum is not smooth, but distinctly wrinkled and dull, you can see very well in your nice pictures.
If you search in this website or google the name, you'll find many
Omalus aeneus to compare the smooth mesoscutum.
Thanks!
Paolo