Bip39 Standard. Though there are BIP39 wordlists in languages besides English, it's strongly not advisable to use non-English words for wallet backups. It would make restoring the wallet complicated or extremely hard. No, there is absolutely no technical limit to your duration of the passphrase. Having said that, for that https://thebookpage.com/story4306343/bip39-generator-https-linktr-ee-bip39-an-unbiased-view-of-bip-39