I ran into this same issue. On my Design Layer, I wanted the Spaces with no fill, but on Viewport, I would like to use Data Visualization to fill the Spaces with colors. When I set the class of the 2D Boundary of the Space to "No Fill," the Data Visualization would not work, even will a Solid fill set in the Data Visualization.
I managed to fix this issue by making the 2D Boundary of the Space Style use a different Class than the Space itself. Then, I could set the 2D Boundary Fill Opacity to 0%, while still having the Pen Opacity at 100%. Using this method, Data Visualizations now work
However, they Data Visualizations do not work when the Class Fill is set to "No Fill." They don't even work when I override the Class settings inside the Viewport themselves.