What's a good plugin to get my comments into the posts RSS feed?

I’m looking to test out running the comments underneath my posts within the primary RSS feed. I haven’t seen too many blogs doing this, but my best example is the Comics Should Be Good blog : https://goodcomics.comicbookresources.com/feed/ (and from what I’ve heard, Slashdot may also do this).

What’s a good plugin for this feature? I’ve done searches but had a hard time finding the right thing. Thx!