Board Thread:Support Requests - Getting Technical/@comment-30964712-20170106051816/@comment-31294034-20170424205942

You cannot play Overwatch on a Chromebook as the platform is not supported by the game's publisher.

This is not something that is going to be changed in the near future.

This thread is also several months old and does not need to be commented on. If you would like to further this discussion then I suggest you head over to the Overwatch wiki and talk to them about it. I am sure you will find more insightful answers on a community dedicated to the game.