Hello Adeleke,
Thanks for your question.
You can do this using backup in the Microsoft Authenticator app.
Go to Settings > Backup.
Enable backup by signing into your Microsoft account.
On the second phone Choose the Restore option to sync your accounts.
However, note that the Microsoft account of the Authenticator has to be same for this to work.
You can also simply just scan the QR code on both phones. (However, this is not going to be providing a backup just a replication)
You can mark it 'Accept Answer' and 'Upvote' if this helped you
Regards,
Abiola