Override translations in child theme for plugins, themes etc.

wp-child-theme-l10n-universal.php

<?php
/**
 * Translations in Child Theme!
 */
if (!function_exists('agk_reload_child_theme_domain')) {
    function agk_reload_child_theme_domain($domain)
    {
        $path = get_stylesheet_directory() . '/languages/';
        $mofile = $path . $domain . '-' . get_locale() . '.mo';
        if (is_readable($mofile)) {
            unload_textdomain($domain);
            load_textdomain($domain, $mofile);
        } else {
            var_dump('Not found: ', $mofile);
        }
    }
}
add_action('after_setup_theme', function () {
    $domains = [
        'woocommerce', // Woocommerce translations don't work so... 
        'woocommerce-germanized'
    ];
    foreach ($domains as $domain) {
        agk_reload_child_theme_domain($domain);
    }
});

// OR:

add_filter('load_textdomain_mofile', function ($mofile, $domain) {
    $domains = [
        'woocommerce',
        'woocommerce-germanized'
    ];
    if (in_array($domain, $domains)) {
        $path = get_stylesheet_directory() . '/languages/';
        $mofileNew = $path . $domain . '-' . get_locale() . '.mo';
        $mofile = is_readable($mofileNew) ? $mofileNew : $mofile;
    }
    return $mofile;
}, 10, 2);

/**
 * END of: Translations in Child Theme!
 */