Any filter turn a color image into a grayscale version?

[VegetationBush (FartedWayTooHard)]

You cannot do this, although, there is a workaround:

1. Put the image as a decal or some other instance that renders in 3D
2. Create a ColorCorrection in the Lighting service
3. Set saturation to 0

Not the best workaround and only works in some cases.