Hi, if you set your view to “unlit”, that means you’re only viewing the color, no post processing, no emissive.
If you set the view to “lit” then you also have post processing and since you’re using emissive color in your material that will also look different.
[HR][/HR]
Since you apparently want to use this for UMG, why not use a widget and set then set the material domain to “User Interface”? Then you will always have the same color.