It would be great to have emojis as a feature for email engagements. FYI -
In this example, the email is sent from Confluence regarding a new release. I've attached a screenshot of the survey (and a 2nd screenshot of the page which appears when the user has interacted with one of the 3 emojis)
I do not see this as a request to add emojis in email engagements. Emails can certainly include emojis as emojis can be easily copy pasted into the content.
I believe the request is actually to allow a survey to be sent from within a PX email engagement (not supported). What you do in PX is ask the user to click a link to take a survey, the link can take them back into your app where an in-app survey is shown.
The Confluence example of an email-based survey is supported on the Gainsight CS platform.