The bug
I could spam right-click as fast as I wanted and throw as many ender pearls as I needed. A .gif for a more visual explanation is provided here: https://gyazo.com/a3ee2feed58606192bb136253bd82239
How to reproduce
Grab an ender pearl in 1.14.4
Spam right click
I'm unable to reproduce this in 1.14.4. Pearls still have the 1 second cooldown in both creative and survival as far as I can tell.