I really like webmentions. They provide a way to let folk know that you're writing about their blog posts. I see them as an alternative to comments which encourages better discourse.
Webmentions can be a pain to manage though, especially if you have a statically generated site like this. For receiving mentions there's the venerable webmention.io service. I use this to collect mentions and then I check periodically and copy mentions over to the metadata of the targeted post.
To dispatch webmentions I made a glitch, which I've written about before. It's closely coupled to the URL structure of my blog and how it compiles webmentions into pages, so I'll stick with it but it's not so useful for others except as a reference.
If you've just decided to include webmentions on your blog, then Remy Sharp created webmention.app to automate searching for links and dispatching webmentions for a page. If I were starting now I'd use it! You can read more about it in Remy's own words.
Jamie Tanna on