Bip39. Even though you will discover BIP39 wordlists in languages apart from English, it is actually strongly not advisable to make use of non-English words for wallet backups. It would make restoring the wallet hard or impossible. No, there is absolutely no technological Restrict towards the length of one's passphrase. https://thebookmarkage.com/story18649854/bip39-wallet-https-linktr-ee-bip39-bip39-wallet-fundamentals-explained