Bip39 tool github https://felixkkjt585.theglensecret.com/bip39-word-checklist-generator-crafting-your-own-special-seed-phrase While it uses BIP32 technique you could still import BIP39 seeds into Electrum wallet. Also other than BIp32 There exists BIP44 Model which some wallet use for the era of seeds. Press X to abort passphrase software and continue to keep modifying the passphrase.... https://jaspermuxp089.yousher.com/top-5-online-bip39-generators-for-effortless-copyright-security