So take a ethernet cable and plug directly into the router to test. Powerline adapters have no concept of what a game is. They pass all traffic the same you should have issues on all game if there was a issue with the units.
It is much more likely it is some setting on your pc not even network related. But your very first step is to connect it via ethernet and if everything runs fine then you can consider the powerline units. Unfortantly there is not much you can do to change how the powerline units run. Some brands may run faster but they all pretty much run a very stable latency.