https://www.pcguide.com/software/how-to/fix-path-of-exile-2-network-spike/
Launch Path of Exile 2.
Go to Options and then select Game.
Click on the folder icon next to ‘Item Filter.’
Folder icon
Now, close the game.
In the folder, open the poe2_production_Config file
Scroll down and find [NETWORKING].
Below it, you’ll see networking_type=auto.
Replace ‘auto’ with predictive or lockstep.
It should look like this: networking_type=predictive