That's pretty cool! Get ready to keep these up to date monthly or become obsolete quickly.
One of the downsides of tools like this is that your URL needs to be available online so if there's an issue, your iteration loop is quite long.
In Polypane [1] I've built social media previews that work with any local URL but also let you overwrite that URL for the social media that display those. I built (and frequently maintain) previews for X/Twitter, Facebook, Slack, LinkedIn, Discord, Mastodon, Discord, Google Search, Bluesky, Mastodon and Threads. For all of those I have the design for their light and dark mode so you really can test everything. It also tells you what's missing and what is incompatible. Check it out: https://polypane.app/social-media-previews/