Several possibilities. For a simple effect try the bump map filter and select spotlight or enter your own values.

I looked at your sample. For a starting point I used the default text under Media Generations, just typed Example and then stretched the event to about 5 seconds.

Now drop in the Bump Map Filter from Video FX

For a rought starting point, try Intensity 400. Focus 500. Ambience 330. Note the work area. For the first key frame move the red cross icon slightly to the left of the yellow square. For the last key frame set the red cross icon slighlty right of the yellow square. Adjust the settings as necessary to get the effect you want.

The above should cause a spotlight effect to slowly drift over the text left to right. Ambience will determine how much of the darkened text shows before hit by the spotlight. A few minutes of playing around should get you close to what you want.