Using Freshdesk, you could send all reply emails to a particular email address. This email address could be configured to be in the BCC of any email sent out of your Freshdesk Account. This could be used for instances where all emails would have to be saved for audit or when the Manager/Lead wants to be in the loop on any conversation.
To automatically add an email address to BCC, navigate to Admin > Channels > Email > Advanced Settings and choose the option that says 'Set automatic Bcc email'. You could add multiple email addresses in BCC, by separating them with a comma(,). For example, you could add them as firstname.lastname@example.org,email@example.com,firstname.lastname@example.org, and so on.
You can also watch this video to know how to setup automatic BCC