ORA-12705: Cannot access NLS data files or invalid environment specified with jmeter test
As per Oracle FAQ

Setting the NLS_LANG environment parameter is the simplest way to specify locale behavior for Oracle software. It sets the language and territory used by the client application and the database server. It also indicates the client's character set, which corresponds to the character set for data to be entered or displayed by a client program.

So you can try explicitly setting user.country and user.language Java system properties, either add the next lines to system.properties file (lives under &quot;bin&quot; folder of your JMeter installation:
user.country=us
user.language=en

or pass these properties via -D command-line arguments like:
./jmeter -Duser.country=us -Duser.language=en -n -t .....

References:

How to change the LOCALE (Language and Country) and TIMEZONE for the IBM Technology for Java (IT4J) VM on the IBM i
Configuring JMeter
Apache JMeter Properties Customization Guide