When starting sqldeveloper 18.1 looking NLS settings in sqldeveloper GUI I found JAPANESE starting with my previous wrap script working well in version 17.4. '-Duser.language=hu' should influence NLS that is working in version 17.4 instead of default JAPANESE seen in GUI.
it means -Duser.language has no effect in version 18.1
Starting without wrap script I found the right setting to language though encodings are different.
start 18.1 from sqldeveloper.exe : --> R:\oracle\progs\sqldeveloper_181\sqldeveloper.exe
starting from wrap script:
(some env settings )
start R:\oracle\progs\sqldeveloper_181\sqldeveloper.exe -J-Dide.splash.screen=splash_t.gif -J-Dide.user.dir=%SQLDEV_DIR%