Why not just show a grid with projects with the search always visible that shows this field? Because it will filter the grid based on this enum you choose. Or am I missing the point here?
Regards,
Ronald
[EDIT]
Create a non persistent object with an attribute with the enum value. Retrieve the projects with the standard value of the enum and attach those projects to the enum and show those. Use an on change microflow on the enum to retrieve again the projects based on the value selected and attach those again.