There are a lot of email notification options on Legalesign. This article explains how to get signed documents copied to the sender and signer(s).
Admin users go to Admin > Signer Experience. Scroll down to 'Email Options'. Find the field called 'Email sender when a document is signed or rejected' and below it 'Email signer(s) when document is signed'.
Each of these options includes two checkboxes to their right. The left checkbox turns the setting on and off, and the right-hand one is the option to "Append PDF". Make sure both boxes are ticked and then press 'Save' at the foot of the page.
Here is a short video to show you how: