Variable font → mouse movement animation

Select the frame named text frame

In the Interact panel, add a new Parametric Animation

Choose the action: Horizontal Mouse Move

Trigger Event: Mouse Move X
→ Click Customize and turn ON Smooth Animation

Area of Action: text frame (the frame selected above)

Layer of Interaction: variable (the text layer)

Choose: Fill, Font Weight

Keep only "Change to" selected

Fill = #9F9FFF (purple)

Font Weight = 900

Duration = 4s

All other settings can remain default

Enable Split Text

Choose: By letter

Set Interval = 0.2