Probably I wasn't explicitly enough.
The main localization file (en):
pakageSHU.properties or pakageDE.properties
-for German (de) :
pakageSHU_de.properties or pakageDE_de.properties
-for Chinese (zh_CN):
pakageSHU_zh_CN.properties or pakageDE_zh_CN.properties
As I've write in the post +(plugin acronym)+:
-SHU mean SelectHideUtility
-DE mean DistributeElevation
-packageSHU name could be whatever you want but it need to be the same for all 18 or more files followed by the country code(_fr, _it, _de etc)
-I've choose this form to distinguished between the same file on different plugins.
In this way a translator could send me multiple files for different plugins at once.

I will publish soon the new version of Distribute Elevation plugin which I intend to use as template.
BTW I've discovered few days ago I've already used the FURNITURE_MENU.Name in this plugin in 2020 but I've forgot.

Sorry for the disturbance!