locale addon does not work

I have Kodi v18.4 on LibreElec 9.1.501 on rpi3

i've install locale addon, switch setting to "en_US.UTF-8" and reboot the device.

but when I run terminal by ssh and execute the "locale" command

i have

locale: Cannot set LC_MESSAGES to default locale: No such file or directory
locale: Cannot set LC_ALL to default locale: No such file or directory
LANG=en_US.UTF-8
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC="en_US.UTF-8"
LC_TIME="en_US.UTF-8"
LC_COLLATE="en_US.UTF-8"
LC_MONETARY="en_US.UTF-8"
LC_MESSAGES="en_US.UTF-8"
LC_PAPER="en_US.UTF-8"
LC_NAME="en_US.UTF-8"
LC_ADDRESS="en_US.UTF-8"
LC_TELEPHONE="en_US.UTF-8"
LC_MEASUREMENT="en_US.UTF-8"
LC_IDENTIFICATION="en_US.UTF-8"
LC_ALL=

in output.

if look from afar, i do this to run the "EmulationStation" from "gamestarter" repo,

and it throws the error

locale::facet::_S_create_c_locale name not valid

here the link to gihub issue EmulationStation on Kodi v18.4 "Leia" · Issue #137 · bite-your-idols/Gamestarter · GitHub

please guide me, what can i check or what try to do with this issue?

i've found the similar issue - Locale charmap ANSI_X3.4-1968 instead of UTF-8 . i think this issue can be related to default libreelec configuration. what can be done to resolve this issue?