Create a “Google Translator” plugin in WordPress

<?php
/*
 * Plugin Name: Google Translate
 * Plugin URI:  https://example.com/google-translate
 * Description: A plugin that uses Google Translate to translate content on your website.
 * Version:     1.0
 * Author:      Your Name
 * Author URI:  https://example.com
 * License:     GPL2
 * License URI: https://www.gnu.org/licenses/gpl-2.0.html
 * Text Domain: google-translate
 */

// Exit if accessed directly
if ( ! defined( 'ABSPATH' ) ) exit;

/**
 * Load the Google Translate API library.
 */
require_once plugin_dir_path( __FILE__ ) . 'vendor/autoload.php';

/**
 * Load the plugin text domain.
 */
function google_translate_load_textdomain() {
	load_plugin_textdomain( 'google-translate', false, dirname( plugin_basename( __FILE__ ) ) . '/languages' );
}
add_action( 'plugins_loaded', 'google_translate_load_textdomain' );

/**
 * Add a settings page for the plugin.
 */
function google_translate_add_settings_page() {
	add_options_page(
		__( 'Google Translate', 'google-translate' ),
		__( 'Google Translate', 'google-translate' ),
		'manage_options',
		'google-translate',
		'google_translate_render_settings_page'
	);
}
add_action( 'admin_menu', 'google_translate_add_settings_page' );

/**
 * Render the settings page.
 */
function google_translate_render_settings_page() {
	if ( ! current_user_can( 'manage_options' ) ) {
		wp_die( __( 'You do not have sufficient permissions to access this page.', 'google-translate' ) );
	}
	?>
	<div class="wrap">
		<h1><?php _e( 'Google Translate Settings', 'google-translate' ); ?></h1>
		<form method="post" action="options.php">
			<?php
			settings_fields( 'google_translate_options' );
			do_settings_sections( 'google-translate' );
			submit_button();
			?>
		</form>
	</div>
	<?php
}

/**
 * Register the plugin settings.
 */
function google_translate_register_settings() {
	register_setting(
		'google_translate_options',
		'google_translate_options',
		'google_translate_sanitize_options'
	);
	add_settings_section(
		'google_translate_section_api_key',
		__( 'API Key', 'google-translate' ),
		'google_translate_render_section_api_key',
		'google-translate'
		);
	add_settings_field(
		'google_translate_field_api_key',
		__( 'API Key', 'google-translate' ),
		'google_translate_render_field_api_key',
		'google-translate',
		'google_translate_section_api_key'
	);
}
add_action( 'admin_init', 'google_translate_register_settings' );

/**
 * Render the API Key section.
 */
function google_translate_render_section_api_key() {
	?>
	<p><?php _e( 'Enter your Google Translate API key here.', 'google-translate' ); ?></p>
	<?php
}

/**
 * Render the API Key field.
 */
function google_translate_render_field_api_key() {
	$options = get_option( 'google_translate_options' );
	$api_key = isset( $options['api_key'] ) ? $options['api_key'] : '';
	?>
	<input type="text" name="google_translate_options[api_key]" value="<?php echo esc_attr( $api_key ); ?>">
	<?php
}

/**
 * Sanitize the plugin options.
 *
 * @param array $input
 * @return array
 */
function google_translate_sanitize_options( $input ) {
	$output = array();
	if ( isset( $input['api_key'] ) ) {
		$output['api_key'] = sanitize_text_field( $input['api_key'] );
	}
	return $output;
}

/**
 * Translate a string of text.
 *
 * @param string $text
 * @param string $source_language
 * @param string $target_language
 * @return string
 */
function google_translate_translate( $text, $source_language, $target_language ) {
	$options = get_option( 'google_translate_options' );
	$api_key = isset( $options['api_key'] ) ? $options['api_key'] : '';
	if ( ! $api_key ) {
		return $text;
	}
	try {
		$client = new Google_Client();
		$client->setDeveloperKey( $api_key );
		$translate = new Google_Service_Translate( $client );
		$result = $translate->translate( $text, $target_language, $source_language );
		return $result['translatedText'];
	} catch ( Exception $e ) {
		return $text;
	}
}

This code creates a plugin that adds a settings page to the WordPress admin area, where users can enter their Google Translate API key. The plugin also includes a function for translating a string of text from one language to another using the Google Translate API.