Custom Laravel Translator that handles locale with region

README.md

In config/app.php in the 'providers' section, replace Illuminate\Translation\TranslationServiceProvider::class with App\Translation\TranslationServiceProvider::class

TranslationServiceProvider.php

<?php
 
namespace App\Translation;
 
class TranslationServiceProvider extends \Illuminate\Translation\TranslationServiceProvider
{
    public function register(): void
    {
        $this->registerLoader();
 
        $this->app->singleton('translator', function ($app) {
            $loader = $app['translation.loader'];
 
            // When registering the translator component, we'll need to set the default
            // locale as well as the fallback locale. So, we'll grab the application
            // configuration so we can easily get both of these values from there.
            $locale = $app['config']['app.locale'];
 
            $trans = new Translator($loader, $locale);
 
            $trans->setFallback($app['config']['app.fallback_locale']);
 
            return $trans;
        });
    }
}

Translator.php

<?php
 
namespace App\Translation;
 
class Translator extends \Illuminate\Translation\Translator
{
    /**
     * Get the array of locales to be checked.
     *
     * @param string|null $locale
     *
     * @return array
     */
    protected function localeArray($locale)
    {
        $locale   = $locale ?: $this->locale;
        $language = locale_get_primary_language($locale);
 
        return array_filter([$language ?: $locale, $this->fallback]);
    }
}