Szwab is so passé, these days it's niemiaszek or simply Fritzl.
- as diminutive - was popular in Polish movies from 60'. Russian soldier used to say: szczęśliwie wyrżnęliśmy wszystkich Niemiaszków
= fortunately we have all Niemiaszeks butchered.Fryc
(not Fritzl) is as old as Szwab
and is 100 yo or more, I believe.
More contemporary was Helmuty
(Helmuts - after Kohl and Shmidt) for Western Germans - not derogative
- after Enerdówek
(let's say Ddrdorfers after Ddrdorf) for Eastern Germans - more paternalistic than derogative.
I haven't heared any new derogative term for Germans since then. It looks things are getting better at last in Poland.