| Set up External Connections using Application Password

Ensure that the current version of Distributor is active on BOTH sites being connected. We'll refer to these as mainsite.com and remotesite.com.

On mainsite.com, navigate to Distributor > External Connections and click Add New.
Enter a label for the connection (e.g., remotesite.com), select Username / Password for the Authentication Method, and a username from remotesite.com.

On remotesite.com, ensure that Application Passwords is installed. (Note: Using this plugin instead of a normal WordPress users password helps limit the use of your primary password and will allow you to revoke access to Distributor in the future if needed.) Then navigate to the user profile that will be used to create the External Connection on mainsite.com and then to the Application Passwords section of the user profile (not the Account Management section). Add a label for the New Application Password Name (e.g., mainsite.com) and click Add New. Now copy the password provided into mainsite.com's External Connections Password field.
On mainsite.com, add the External Connection URL (e.g., http://remotesite.com/wp-json). You should see a green circle and "Connection established.".

Ensure the roles selected in Roles Allowed to Push are the ones you want to support, then press the Create Connection button. You should now be able to push from mainsite.com to remotesite.com. If you want to pull from remotesite.com to mainsite.com, simply repeat these instructions swapping mainsite.com and remotesite.com.