Bip39 recovery phrase http://www.mediafire.com/file/uilrjfajg2ami24/pdf-14673-57158.pdf While it takes advantage of BIP32 technique you'll be able to nevertheless import BIP39 seeds into Electrum wallet. Also other than BIp32 There may be BIP44 Model which some wallet use for your era of seeds. How much security does a passphrase insert? A BIP39 passphrase https://health-lists.com/story21241644/bip39-standard-indicators-on-bip39-standard-you-should-know-https-x-com-tundra838554