Hi! I had a idea! If you have ever done art design on the new animal crossing, Animal Crossing New Horizon, then you know about the drawing-duplicator, or in easier terms, the tool that doubles what you are drawing to the other side. I think Scratch could benefit from such a tool, because then people could copy designs and draw pictures out easier as well! You could also have an easier time perfecting head shapes and body designs!
In short, I believe it would make art easier and cleaner, and that it would make animation for all us animators out there simplier and quicker, so we could post projects faster and more effeciently!

-StinkoRH

It is workaroundable.
Copy > Paste > Align to original image > flip vertically