Hi! There are lots of ways to do this and it kinda depends on what you need. The simplest "elegant" solution is to run Prodigy on a remote machine/server on a given port and open up that port. You can then send your annotators the URL of your remote machine. If you want this to be nicer, you can add a domain to it.
The simplest "quick and dirty" solution would be to use a service like ngrok or localtunnel to expose your localhost via a public URL. This means you can run Prodigy on your local machine and make it accessible via a private link, and as long as it's running, others can annotate on your machine.