According to "Main menu":
"Network" calls the command 'network-admin' and its description is "Configure
network devices and connections";
"Network Connections" calls the command 'nm-connection-editor' and its
description is "Manage and change your network connection settings";
"Online Accounts" calls the command 'credentials-preferences' and its
description is "Online account credentials and settings";
The other "Online Accounts" calls the command "gnome-control-center
online-accounts" and its description is "Manage online accounts".
They are all different commands. You can decide that you will never use one
of them and simply make it disappear from your menu in one click on a check
box in "Main menu".
