Magento 2 – How to Translate Only the Storefront

Step 1: collect the phrases

First, you need to find out the phrases that you need to translate.

You can do so by running:

php bin/magento i18n:collect-phrases -o "/path/to/magento2/app/i18n/vendor/lg_lg/dictionary.csv"

Note that vendor is the same as when you develop module and lg_lg is the lang code of your language.

Step 2: create the composer.json file

Go to your app/i18n/vendor/lg_lg folder and create the composer.json file:

{
    "name": "vendor/lg"
    ,"type": "magento2-language"
    ,"description": "Tamil language"
    ,"authors": [{
        "name": "Bilal Usean",
        "email": "bla@bla.com",
        "role": "Developer"
    }]  
    ,"extra": {"map": [["*", "vendor/lg_lg"]]}
}

Step 3: create the language.xml file

Still in your app/i18n/vendor/lg_lg folder you need to create a language.xml file:

<?xml version='1.0'?>
<language xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xsi:noNamespaceSchemaLocation='urn:magento:framework:App/Language/package.xsd'>
    <code>lg_LG</code>
    <vendor>vendor</vendor>
    <package>lg_lg</package>
</language>

Step 4: create the registration.php file

Still in the same folder, you need to create a registration.php file:

<?php

\Magento\Framework\Component\ComponentRegistrar::register(
   \Magento\Framework\Component\ComponentRegistrar::LANGUAGE,
   'vendor_lg_lg',
   __DIR__
);

Step 5: translate

Still in your folder, you can start writing your translations in a lg_lg.csv file based on the dictionary you retrieved in step 1. You can use the offical guide to follow the translation guidelines: http://devdocs.magento.com/guides/v2.0/config-guide/cli/config-cli-subcommands-i18n.html#config-cli-subcommands-xlate-dict-trans

Step 6: create the language pack

Run the following command:

php bin/magento i18n:pack app/i18n/vendor/lg_lg/lg_lg.csv lg_Lg lg_LG

Important note

For this to work, your .csv file name must exactly match the locale, including the characters' case.

Official documentation: http://devdocs.magento.com/guides/v2.0/config-guide/cli/config-cli-subcommands-i18n.html#config-cli-subcommands-xlate-example2

You can use the locale emulation for this:

$storeId would be the ID of another store with the specified language that you want to use.

$locale = Mage::app()->getLocale();

$locale->emulate($storeId); //push current locale to stack and replace with locale from specified store

//your magic here

$locale->revert(); //use last locale before last emulation