There are no German translations provided by us for Custom Properties.
You can write your own translations.
===
Frontend
1) copy file:
components/com_customproperties/language/en-GB/en-GB.com_customproperties.ini
to
components/com_customproperties/language/de-DE/de-DE.com_customproperties.ini
2) edit the copied file and translate the file (only those strings on the right side of the 'equal' sign).
Mod CPSearch
1) copy file:
modules/mod_cpsearch/language/en-GB/en-GB.mod_cpsearch.ini
to
copy file modules/mod_cpsearch/language/de-DE/de-DE.mod_cpsearch.ini
2) edit and translate
Backend
1)
copy file:
administrator/components/com_customproperties/language/en-GB/en-GB.com_customproperties.ini
to
administrator/components/com_customproperties/language/de-DE/de-DE.com_customproperties.ini
2) copy file:
administrator/components/com_customproperties/language/en-GB/en-GB.com_customproperties.sys.ini
to
administrator/components/com_customproperties/language/de-DE/de-DE.com_customproperties.sys.ini
3) edit and translate both files
