Most slavic languages are fusional, whereas Finno-Ugric and Basque are agglutinative. That's why the "feel" of both groups' cases is different You could even argue that the term "grammatical case" is rather ill-fitting for agglutinative languages, and makes them look way scarier than they should be, bcs they have "13 cases" haha

I don't know anything but I do think Hungarian can sound like Japanese/Korean because some cases can look like postpositions. As to Sinitic, let me answer that 介詞 are adpositions and can be pre- or postpositions. And given that there is no space in Sinitic languages, why else, would you think, it took so much time for Google translate to have Cantonese due to the work on delimiting word and grammar boundaries and from Mandarin. Hungarian or Slavic or European usually have no such issues.