Live Profile Cards are a standard for the inline People experience in Office 365. Dynamics 365 users are now part of this coherent experience, as end users in Unified Interface can hover over lookup fields featuring contact entity and view details of that contact in Common Data Service as a live profile card.

  • End users can quickly look up details of a contact record without navigating to the contact form.
  • End users can start a quick call, email, or IM with their contacts

Profile Contact Hover Dynamics 365

The information shown on the contact profile card is fetched from Common Data Service (and not Microsoft Exchange). This means the contact details are coming from Dynamics 365. Currently, the list of fields displayed on the profile card are not open for customization.

Administrators have the option to turn off profile cards for their organization under

Administration > System Settings > General tab

Please Contact-Us for any further question or support elements

References: 
https://docs.microsoft.com/en-us/powerapps/user/profile-cards

https://docs.microsoft.com/en-us/business-applications-release-notes/april19/microsoft-powerapps/office-value-adds-dynamics-365