Android ScrollView clipping child elevation shadow
I was facing the same problem, I solved it by adding cardUseCompatPadding attribute to the card view:
app:cardUseCompatPadding="true"
The shadow will not be cut out or cropped after using this solution.
this just worked for me in a similar problem:
the right way to get a child view to show shadow is to set padding on the parent and set android:clipToPadding="false" on that parent.
as found here: Android "elevation" not showing a shadow