Bip39 Passphrase. Despite the fact that you will discover BIP39 wordlists in languages besides English, it can be strongly not advisable to implement non-English words for wallet backups. It would make restoring the wallet difficult or impossible. At its Main, a BIP39 passphrase modifies the cryptographic technique of wallet technology. https://travialist.com/story9754155/bip39-generator-https-linktr-ee-bip39-bip-39-no-further-a-mystery