Bip39 Passphrase. Though you will find BIP39 wordlists in languages in addition to English, it can be strongly not advised to use non-English words for wallet backups. It would make restoring the wallet complicated or difficult. BIP39 specifies a list of 2048 words from which the mnemonic phrase is chosen. https://tealbookmarks.com/story18811581/bip39-word-list-pdf-https-linktr-ee-bip39-an-unbiased-view-of-bip-39