sir, i want to make 3d spritesheet with transparent background, which look at camera & in keyframe based. shall i follow example in Basic_UVAnimation or Basic_SpriteSheetAnimation ? i think Basic_SpriteSheetAnimation example more controllable, but how to make background transparent ?

have you tried setting the alphaBlending property on the material?

can we make use SpriteSheet data from XML like AtlasTexture Starling ?

yes, and the spritesheet helper will handle it, but at the time it was made the shader handling the cells did not support compressed cells.
In other words inner rects per cells rects are not supported.
I recall there were at least 2 posts with code example on how to define and load the xml in this forum.

As a side note, I worked on new tools around spritesheets for Prefab, while the principles of the away3d api may look more complex than in some other frameworks, it was flexible and extensible enough for me to generate/edit/playback tools for simple and complex animations without any mods…
Just to say that unless you plan use tons of animations, it’s so easy to define them, that I would consider play around a bit more.