As you can guess, we are going to need a plugin. A handy plugin called Comments Like Dislike ...

Here it is:

https://wordpress.org/plugins/comments-like-dislike/

And this time I can't say that is a "tiny" plugin ... It's a 1.15 MB plugin, so before anything else, let's see the usual speed tests ...

Here are my results before installing the plugin ...

... and the result after installing and activating the plugin:

Which means an additional 6 ms ... In other words, 0.006 second ... So i'ts not a tiny plugin, but is definitely a well-coded plugin! No more comment needed I guess ...

With that having said, let's see how it works ...