(*Example:Whiletheumlautinthechartlegendisshowncorrectly,theoutputPDFfileiswrong*)​​$CharacterEncoding​​chart=BarChart[{1,2,3},ChartLegends->{"Umlaut Ä","Umlaut Ö","Umlaut Ü"}]
Out[]=
UTF-8
Out[]=
Umlaut Ä
Umlaut Ö
Umlaut Ü
In[]:=
Export[FileNameJoin[{NotebookDirectory[],"chart.pdf"}],chart]
(*ExpectedResult:APDFwiththerightUmlaut,Ä,Ö,Ü.ButIget:¥,¦*)