The Translate tool allows you to manipulate the X and Y coordinates of a selected object. Press T to activate it.
With an object selected, click and drag in the empty area of the Stage.
Translate drag

Translate Multi Handles

The Translate tool is the only tool that shows multiple handles. This allows you to quickly manipulate translation, rotation, and scale.
Use the handles to limit your movements to just one axis.
Multiple handles
Hold SHIFT to lock the Scale proportions.

Axis Options and Handles

By default Rive displays translate handles in Local space. Switching to World or Parent coordinates will update the handles accordingly. The Inspector panel will continue to show Local coordinates regardless of what axis options are enabled for the handles. This is because all animation is done in Local coordinates.