Instead of sending notes to a Slack channel, there is the option to use the Fellow Slack bot to send notes directly to a person in Slack.
To do this, click on the "Send Notes" button in the upper right hand corner of the note. Then select the option to "Send via Slack".
Type in the name of the user or select their name from the drop down. (note: the @ and # are just Slack conventions, do not include them in the search).
Feel free to add in a custom message.
The notes will be sent by the Fellow bot to the user, meaning that the notes will show in the recipient's Apps section in Slack, as opposed to your direct message history.
And if you added a custom message, that will appear at the top of the note.