Can I export the same artboard as PNG, horizontally and vertically at the same time?

Can I export the same artboard as PNG, horizontally and vertically, simultaneously?

I need to export for Digital Led Screens, which usually have a 9:16 ratio, but some accept the file only exported horizontally (16:9). 

I tried rotating files on Preview (Mac), but the Digital Led Screen still doesn't accept them. They have to be exported initially horizontally from Adobe Illustrator.

Rotating the artboards and artworks is quite a hassle because I have many artboards, so I was checking for a way to do this without much trouble.