Everything in the app, including grain, works exactly the same for video frames as it does for still images. There may be a limit on the number of seed values for generating the grain pattern and that could potentially be an issue with video although I haven't observed that myself. I'll keep an eye on it!

Yeah same here its mostly noticeable when playing back. Tha tmakes it look like said overlay. Could be the way the grain works in this tool in general. maybe too random and not connected to the previous frame grain makes it look like that

It looks organic still but less organic and more like overlay with playback