There are several popular auto translation plugins for WordPress, here are some of the best:
WPML (WordPress Multilingual Plugin) – a premium plugin that offers a full translation management system for your WordPress site.
Polylang – a free plugin that allows you to create a multilingual website in WordPress with ease.
Google Language Translator – a free plugin that uses Google Translate to automatically translate your website into multiple languages.
ConveyThis – a premium plugin that provides automatic translation and allows you to manage your translations directly from your WordPress dashboard.
TranslatePress – a free plugin that provides automatic translation and a user-friendly interface for managing translations.
These plugins are highly rated by users and offer different features and customization options. You can choose the one that best fits your needs.