Design an AI system capable of understanding and analyzing content across multiple languages and modalities (text, images, video, audio) for applications like global content moderation, cross-cultural marketing, and multilingual information retrieval. Focus on implementing cross-lingual representation learning, multimodal fusion techniques, and transfer learning for low-resource languages. Address challenges like aligning representations across languages and modalities, handling cultural nuances and context, scaling to hundreds of languages, and providing real-time analysis for large volumes of global content.