In the GameUserSettings.ini there's 'XPMultiplier'. Change that and you'll override the 'master' xp gathering.
Instead of changing the amount of XP needed per level you just change how fast you get the XP with that.
I've had a friend who is trying to join my server but he gets kicked by battleye after 5 minutes of being in the server.
I've googled it a bit but couldn't find a solution, anyone has an idea how to fix this?