https://bugs.winehq.org/show_bug.cgi?id=45148
--- Comment #11 from odzinic@gmail.com --- I came across some other users reporting this on other websites. Both of them were using a Corsair keyboard so I'm wondering if it might have something to do with that. I'm using a Corsair K90.
A user also mentioned that when they used a program to virtually switch the left and right control keys Overwatch still recorded LCONTROL as RCONTROL but they were able to use the swapped control key on the left. Not sure if this helps.