Brid.gy, one of my side projects, backfeeds comments on social networks to web pages linked in the posts. It only supported WordPress when I launched it a couple years ago, but I’ve been making some changes, and it now sends webmentions instead, which are supported in lots of servers. I also added Instagram, made a bunch of smaller improvements, and updated the look and feel. Check out this example of backfed comments, then feel free to try it out yourself!
The update was inspired by the IndieWeb community, who have been doing all sorts of great work around making personal web sites a viable alternative to social network profiles. Thanks all!