Bip39 react https://andersonsaeu988.iamarrows.com/bip39-generator-online-the-best-devices-for-secure-wallet-creation Although it utilizes BIP32 strategy you may continue to import BIP39 seeds into Electrum wallet. Also aside from BIp32 There is certainly BIP44 Edition which some wallet use for the era of seeds. For words that have only three letters, there's no 4th letter. As an example https://x.com/Tundra838554