I'm using ArcGIS Pro. I have developed a model and want to document it in an image or some other format (in case I goof it up in later edits). Besides screen capture, is there an easy way to "print" a model diagram?
I do not believe Pro includes this functionality, although it has some neat new ways to examine and save a model in XML format. Kind of a new more comprehensive way to document what's in your model...
ModelBuilder Report—ArcGIS Pro | ArcGIS Desktop
Not exactly the best answer you wanted, I'm sure, but you can save the toolbox to ArcMap 10.5 format, open it in ArcMap and print from there. I bet you'd need to do some cleanup though as the graphic environments are different. This is also the only current way to export a model to a Python script.
Add Export Model to Python Script back to ArcGIS Pro
This page summarizes differences between the ArcMap and Pro ModelBuilder:
ModelBuilder: migration to ArcGIS Pro—ArcGIS Pro | ArcGIS Desktop
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