Bip39-Standalone. The passphrase is not picked from your predefined list of 2048 words – it could be any word or phrase you select. BIP39 is usually a design and style implementation that lays out how copyright wallets make the list of words (or "mnemonic codes") that make up a mnemonic https://thesocialintro.com/story4403225/bip39-mnemonic-https-linktr-ee-bip39-bip39-word-list-pdf-no-further-a-mystery