translating default mo file

Hi, I would like to have default translations in my theme

that involves redefining location of languages folder in functions.php (because I only want to do this for a specific theme)

I have tried a few hours but can’t find the solution

anybody can figure this out ? here is what I have tried:

add_action('wp_loaded', 'my_theme_setup', 0);
function my_theme_setup(){
    load_theme_textdomain('default', get_template_directory() . '/languages/');
   // echo get_template_directory() . '/languages';
 define( 'WP_LANG_DIR',  get_template_directory() . '/languages/' );

}