[Streetplaya]

Try something like this?

pawn Код:

#define LANG_DE 1
#define LANG_EN 2

#define WELCOME_DE "Willkommen"
#define WELCOME_EN "Welcome"

#define SetLanguage(%1) \
    language = %1

#define GetLanguage() \
    language

#define PrintInLanguage(%1) \
    if (language == LANG_DE) \
      print(%1_DE); \
    else if (language == LANG_EN) \
      print(%1_EN)

new language = 0;

public OnFilterScriptInit()
{
    SetLanguage(LANG_DE);
    PrintInLanguage(WELCOME);
    
    SetLanguage(LANG_EN);
    PrintInLanguage(WELCOME);
    return 1;
}

Note: I've made it for console testing only, so just one language variable.