Bip39 Format Despite the fact that it takes advantage of BIP32 method you may however import BIP39 seeds into Electrum wallet. Also besides BIp32 There is certainly BIP44 version which some wallet use for that era of seeds. You may see the full source code in standalone, offline html file. https://socialmediainuk.com/story19843518/bip39-trust-wallet-bip39-for-dummies