The kicad sources contain files for translating the user interface into different languages. But these files are not installed when compiling. Is it possible to include an additional CMAKE_ARGS= option in the port's Makefile to build and set these files by default? As far as I know, this is the -DKICAD_BUILD_I18N=ON option.
But even if you use option -DKICAD_BUILD_I18N=ON, the language translation files are compiled but not installed with `make install`. You need to navigate to the directory /usr/ports/cad/kicad/work/.build/translation/ and run the command `make install` again. Why so, I don't know.