In order to get current content translations of the current post in MultilingualPress, you can use the Translations class passing the arguments via TranslationSearchArgs. Here is an example:
add_filter('the_content', function($content) {
    $args =
        \Inpsyde\MultilingualPress\Framework\Api\TranslationSearchArgs::forContext(
            new \Inpsyde\MultilingualPress\Framework\WordpressContext()
        )->forSiteId(get_current_blog_id())->includeBase();
    $translations = \Inpsyde\MultilingualPress\resolve(
        \Inpsyde\MultilingualPress\Framework\Api\Translations::class
    )->searchTranslations($args);
    foreach ($translations as $translation) {
        $postId = $translation->remoteContentId();
        $title = $translation->remoteTitle();
        $url = $translation->remoteUrl();
        $language = $translation->language();
        $bcp47tag = $language->bcp47tag();
        $englishName = $language->englishName();
        $isoCode = $language->isoCode();
        $locale = $language->locale();
        $name = $language->name();
    }
    return $content;
});
Now you can loop through the $translations array where each Translation object contains translation data and language information.
