Instant alternative to CapturePreviewAsync: Capturing CSS Animations in WebView2: Seeking Efficient API

[antoninononooono]

Imagine WV2 renders an animation like this: https://codepen.io/ndrpssdnt/pen/XWBxbwm

I want to grab the rendered image with its alpha image and render it anywhere on the screen.
This works by using for example CapturePreview and then blitting this alpha channel image anywhere on the screen.

However, CapturePreview is not instant.
I am looking for a way to almost instantly get access to this image.

Is there an API existing for that?

Thank you.