Polyglot от srtk

Polyglot is designed for real-time translation of chat messages. The extension is ideal for language learners seeking to immerse themselves in their target language or for individuals seeking to communicate despite the language barriers.

Users need to add their own DeepL API key in the extension popup which they can generate from https://www.deepl.com/your-account/keys

NOTE: Currently it only works with Element (Matrix) and WhatsApp but support for other apps is currently in development.