I am working on a crypto wallet which supports both Bitcoin and Monero. Wallet first generates a BIP-39 mnemonic and after that mnemonic is used to generate a public and a secret key for Bitcoin.
I want a similar thing for Monero but using the same Mnemonic which is of 12 words. I know how to generate wallets keys and address from 13-word Mnemonic using mymonero-core-cpp code.
So in short my question is that "Is there a way to convert the BIP-39 12 words mnemonic to 13 words mnemonic by appending the checksum or whatever Monero uses in its protocol"?