How to Make an Object Visible Through All Obstacles Except One Specific Cube?

In Unreal Engine, is there a way to make a cube (Cube A) appear see-through (visible even when behind objects) but still allow it to be blocked by a specific object (Cube B)?

For example, enabling “Disable Depth Test” in the material does give me the see-through effect I want. However, I want to add a condition: Cube A should remain visible when behind most objects but still allow it to be blocked by a specific object (Cube B)

Most tutorials suggest using Post Process Volume (PPV) + Custom Depth, but they only modify the object’s overall color based on depth information. However, I want Cube A to retain its original color even when it is partially or fully occluded.

I also considered using PPV without Disable Depth Test and tried to access SceneTexture:PostProcessInput0 in a post-process material to capture the current screen color. However, it seems impossible to retrieve the original color of the occluded Cube A.

Is this effect achievable in Unreal Engine? Thanks!