The Verdict: Clear Path
You can take a working holiday in Germany, but you must apply before travelling at one named German post. Find yours below; no other mission will accept the application.
Where you apply depends on your passport:
Brazil: a German mission in Brazil.
Republic of Korea: the German Embassy in Seoul. The age limit for Korean passport holders is 34, not 30.
Taiwan: the German Institute Taipei.
Hong Kong: the German Consulate General in Hong Kong.
Expect to show funds to support yourself at the start and health insurance covering the whole stay.
The permit lasts up to twelve months and lets you work. It does not convert into a skilled worker permit, and time on it does not count towards the five years needed for naturalisation.