Bip39 specification https://rentry.co/p68weyby A BIP39 seed phrase produced with appropriate randomness can not be guessed through brute force, because there are actually simply too lots of permutations. If another wallet does not support a derivation route that the first wallet supported, that does not necessarily mean your cash are missing. https://greatbookmarking.com/story20504162/bip39-flutter-a-simple-key-for-bip39-github-unveiled-https-linktr-ee-bip39