How do I recreate this bouncy effect?
This is called "Inertial Bounce" and has a handy expression to do all the work!

https://gist.github.com/animoplex/aafd6a157282351c8dfeea385d969ef2

amp = 5.0; freq = 2.0; decay = 4.0;

n = 0;
if (numKeys &gt; 0) {
  n = nearestKey(time).index;
  if (key(n).time &gt; time) { n--; }
}
if (n == 0) { t = 0; }
else { t = time - key(n).time; }
if (n &gt; 0 &amp;&amp; t &lt; 1) {
  v = velocityAtTime(key(n).time - thisComp.frameDuration/10);
  value + v*(amp/100)*Math.sin(freq*t*2*Math.PI)/Math.exp(decay*t);
}
else { value; }


Here's a quick video tutorial as well:


                
            

Hope this helps you out!