Animating along a curve

I want to do a layer animation along a curve movement (picture a circle moving to draw a smile). I can choose a start point and an end point, and I can give ease ins and outs, but it seems it can only move in a straight line. Are there any options here?

thank you

I asked support about this very same question. The short answer is, no, you can’t animate a drawing or a 3D object along a curve. This would require the ability to keyframe the drawing or 3D object. The only thing we can keyframe in STBP is the camera.

A work-around can be achieved with this method. It mean more panels, not to mention more (needless) time spent, but it would get it done:
https://forums.toonboom.com/toon-boom-storyboard-family/general-discussion/sbp4-make-end-3d-xform-settings-1-panel-start-setting#comment-32540