Is it possible to use Cloudflare Workers to handle Dynamic DNS updates for my WireGuard server?

Yes, Cloudflare Workers can be used. You can create a Worker that receives requests (e.g., from a script running on your network) containing your current IP address. The Worker then uses the Cloudflare API to update the DNS record. This approach keeps your API key on Cloudflare's infrastructure, reducing the risk of exposure on your network. You'll need to configure the Worker to allow requests from your network and handle authentication.