Japan and China are two pairs of shoes for Korea and I don’t know, what Germany has to do with this topic. 
China and Korea have and had so many things in common, so in the times of King Taejong it was pretty normal, that the clothes, furniture and ornaments were similar. Joseon was “brandnew” and the Hangul wasn’t even established. During the former Goryeo dynasty it was common, that the kings and princes had to marry Chinese princesses. So the royal Korean families and nobility wasn’t even pure Korean, but Manschurian (it was the Yuan Dynasty) and also Kitan (Kingdom Liao, which invaded Goryeo two times). As an international viewer, I can’t understand, why people react so sensitive, because this is part of their history and their inheritance and they can’t cut the Chinese legacy out.
Japan and Korea is another topic, after what happened during WW 2 with the Comfort Women when over 200,000 women were literally enslaved. And this was not the first time, in the Ceramic Wars Japan enslaved estimated more than 200,000 artists and potters, which had a huge influence on the famous “Japanese pottery”. But during this war the goal was to rob skills and knowledge, in the WW2 the goal was to destroy the nation of Korea, to break their pride and soul, so they forced the women into sex camps, even young girls of 10 or 12 years. A very dark spot in Japanese history and a topic which is far away of being resolved, since the Japanese government has deleted all information about this from the history books in school and does not acknowledge their guilt.
In 2020 a statue of a comfort woman was put up in Berlin, this is the first in Germany and there was a huge discussion, even the Japanese Government with Katsunobu Kato demanded to remove the statue. I’m very proud that the Government in Berlin refused and kept the statue.