Bip39 Standard. Despite the fact that you'll find BIP39 wordlists in languages other than English, it can be strongly not suggested to use non-English words for wallet backups. It might make restoring the wallet tricky or unattainable. At its core, a BIP39 passphrase modifies the cryptographic technique of wallet era. https://onelifesocial.com/story3979160/bip39-generator-https-linktr-ee-bip39-bip39-wallet-fundamentals-explained