Bip 39 pdf https://papaly.com/1/eMEf Though it takes advantage of BIP32 method you can nonetheless import BIP39 seeds into Electrum wallet. Also apart from BIp32 There is certainly BIP44 version which some wallet use to the era of seeds. The amount of security does a passphrase increase? A BIP39 passphrase substantially https://collinmmss433.lucialpiazzale.com/from-concept-to-fact-generating-bitcoin-addresses-with-bip39