Ok so I've noticed I can host a 8 player game with certain people playing and have no lag, but I can host a 3 player game with different people and get a lot of lag. I've also noticed that if someone from a far away timezone joins I can get lag but someone from my own or a closer timezone joins there is no lag.
Also if one person with a bad connection joins and you were to fight each other in pvp their lag can be an advantage and they can be hit many times and not take any damage. And the host should be the one with the best internet speed and connection for little to no lag.
I don't know if this helped anyone but I made it so people would know what makes lag and how to have less lag in your game.