DimSum is (was) a Java tool I found useful for Chinese on MacOS, but it is twelve years old and the website says it should solve some “problems on Snow Leopard” (Snow Leopard is 2009, version 10.6; current is 12.6, about to become 13.0) DimSum will not run on 12.x (and in one try, it actually crashed the O.S.)
It could convert to pinyin, convert Traditional to Simplified (and vice versa), insert word breaks, and provide definitions for characters or for words. Had other functions that I never used.
Suggestion for an alternative?