alan_langlois I actually had the same thought some time ago, and I also found that "SpriteWidget" project.
Flutter is great for standard apps, but the whole reactive approach is not well suited for games. Having a widget that simply opens up the world for a standard Flash-like display list is a very charming idea, because it would let game developers use all of the great infrastructure that's provided by Flutter, and create their games in with, with an approach they are already familiar with.
(Basically, that sounds eerily similar to the idea of Sparrow, when [10 years ago, oh my!] I wanted to add a game development UIView
layer to iOS.)
Technically, Flutter uses the Skia Graphics Library for all rendering, so that's how drawing would need to be done. Flutter provides a "canvas" object which (I think) provides access to those lower level routines.
So, I think it porting Starling to Flutter/Skia would be doable, and I actually like the idea very much! However, I personally can't take on a project like this at the moment, due to lack of time and budget. However, it would be a fantastic side project once I've got a little more time on my hands ... or someone else!! π
On the other hand, it seems like SpriteWidget and Flame could already be very useful and close enough to what's need for Starling developers, so that's definitely something to try out or support, too!