You can't be serious.. How long have you guys been server admins really?
"both Lords recommend players to try turning off your computer’s firewall during the time you are taking part in Sage World Battlefields. By doing so, it will ease the connection to other players."
This has nothing to do with the client's firewall. Traffic towards Naruto is allowed by default unless you sit behind some mean IPS (Intrusion Prevention System) with content detection or a wacky outbound web proxy at work. If so, need should ask their local network security department at work to open up for Naruto to begin with.
If the firewall was the source of the problem, the user would not be able to play the game at all.
This will not ease or make the connection for other players more difficult. Naruto Online relies on a typical hub-and-spoke setup which makes all user communicate directly with the naruto servers instead of user A from connects with user B.
This problem is more likely due to poor internet connections, since the client need to download a bunch of information when loading a new zone, before and under a fights.
Regards Kaguya Ōtsutsuki from 101 networking