You can play your cooldown animation with infinite loop, and then, when cooldown is off, stop it and (optionally) reset to default state. I’ve created an example for you:
In this case, if you press 1 (let’s say you have a cool OP skill binded on ‘1’ key and want to use it) it will play cooldown animation and stop playing it exactly after skill cooldown is down (just hook up your delay variable into ‘Duration’ pin).