How? You're talking about a transaction from a year ago that pays 1 sat/vbyte, while the purging limit is 6.21 sat/vbyte.

Importing your private keys into Electrum wallet
[TUTORIAL]getting a low-fee transaction unstuck by creating a CPFP with electrum

Two guides to do that, first import your private key from Bitcoin Core wallet to Electrum wallet, then use Child Pay For Parents with Electrum wallet.

I think you can do that by just enabling the unconfirmed change on the settings but I don't know if it will work on the output that came from other wallets.

However, in case if it does not work you can generate a PSBT transaction from Electrum just import the BTC address from your Bitcoin core wallet to Electrum and then make a transaction there and send it to any address or send it to the same address(Your BTC address) once you created a transaction save it into .PSBT and sign it to your Bitcoin core wallet and broadcast the transaction.