In theory Markdown Easy supports images. However, to do this the exact URL of the image is required, and Drupal and Markdown Easy don't provide an easy way to get this. Offsite images are okay, but if image filters are being used, it can be hard to get the URL of the filtered image, and without proper integration with the Drupal image/media system, Drupal doesn't know a specific version of the image is being used, so it may not regenerate the image when needed.
At a basic level, it would be fantastic if Markdown Easy could support Drupal media module. I would like to be able to reference a Drupal media entity, and ideally specify an image filter.
E.g. 
That would tell the Markdown image to use the numbered media entity and apply the named image style.
However, my dream solution would be to have a Markdown easy toolbar, with a "media" button that would pop up a media browser and let you select or upload an image (or other media), and insert the appropriate markdown.
Active
2.0
Code
Dries mentioned a similar idea that he had implemented via a custom module - see https://dri.es/switching-to-markdown-after-20-years-of-html
These tokens get processed by my custom Drupal module and transformed into full HTML. That basic image token? It becomes a responsive picture element complete with lazy loading, alt-text from my database, Schema.org support, and optional caption.