Bip39 flutter https://blogfreely.net/travenmdoq/create-your-own-distinct-bip39-mnemonic-expression-with-python-scripts While it employs BIP32 approach you could nonetheless import BIP39 seeds into Electrum wallet. Also aside from BIp32 There exists BIP44 Variation which some wallet use to the generation of seeds. Not like standard wallets derived only from a seed phrase, passphrase-sh... https://binksites.com/story10535829/bip39-hardware-about-bip39-2048-words-https-x-com-tundra838554