It turns out finding the violations for 'layout-animations' policy at the time CSS resources are being parsed is a bit tricky. Naturally, CSS code such as:
{
  transition: width 1s;
}
is a "good" case where we can lawfully generate a report for. However, code such as
{
  transition-duration: 1s;
}
would potentially cause animations for all the banned properties; e.g., when followed up by something like:
div:hover {
  width: 200px;
}

There are other perhaps other subtitles we need to consider.