How can I create a responsive email design in Adobe InDesign?

Answer 1

There's a subscription-based plugin for InDesign called in5 that should help. Check it out here: https://ajarproductions.com

Answer 2

You can design the email look and style in Indesign. But you will have to transfer the final output to Photoshop for the exporting of the images for web. This can be done as a JPG to get into Photoshop.