Hey, Shadow! Did you check the keybindings in Overwatch and for the Hero if its happened specifically on one Hero? It can help to try resetting the in-game settings back to default to be sure. Could you try closing background applications to ensure it’s not a background application? We’ve seen this recently due to third party applications. It may be one that we haven’t called out or seen yet.
If it continues, please contact our Technical Support team directly with both system files so that we can check for any applications that could cause the movement key issue.
Edit: We have a main thread for this report here.