Would love to see a way to prototype for different screen but not to copy paste and adjust the size - make it like in Indesign that we can link files to different sizes.
Have a tool that can collect the assets and place them together into a different scree.
Zach Bruce commented
I would not want this to be a part of Xd's core. I think going down this road (as previous applications like Macaw, Adobe Edge Reflow did) results in more a confusing and difficult to manage interface than speed. I do however would like extensibility to allow for Responsive Resizing as Sketch has.
Sounds like this is similar to this request: