Bip39 Mnemonic. Although there are BIP39 wordlists in languages aside from English, it is strongly not advisable to implement non-English words for wallet backups. It would make restoring the wallet hard or unattainable. Yes, BIP39 passphrases are case-sensitive. You should definitely enter your passphrase specifically as you established it up, https://onelifesocial.com/story4833546/ian-coleman-bip39-https-linktr-ee-bip39-getting-my-ian-coleman-bip39-to-work