Bip39 algorithm https://collinmmss433.lucialpiazzale.com/from-concept-to-fact-generating-bitcoin-addresses-with-bip39 Although it utilizes BIP32 strategy you may nonetheless import BIP39 seeds into Electrum wallet. Also in addition to BIp32 There may be BIP44 version which some wallet use for that era of seeds. How much protection does a passphrase include? A BIP39 passphrase noticeab... https://thesocialdelight.com/story6001909/bip39-offline-new-step-by-step-map-for-bip39-github-https-dzen-ru-bip39-phrase-com