Use URL field to populate Image in a Email Template

Use URL field to populate Image in a Email Template

We have two records
Record 1: Appointments (with a Lookup to Doctors module)
Related Record 2: Doctors (with a URL field that is an image of the doctor)

We would like to populate a CRM email template with the image of the URL field for the related doctor of the appointment that is triggering the workflow launching the template. 

Is that possible using only block builder email templates? Or is that possible with HTML? Can't figure out how to use the image of the URL Field as an image inside the email template. Any advice will be really apreciated.