Many competitive gamers use stretched resolutions + fov adjustments in order to provide competitive advantages in certain games. Changing the FOV value makes targets bigger or smaller, and switching off of a native resolution stretches models horizontally so heads are easier to click on, and narrow pixel peaks are wider.

My problem, is finding a 16:9 fov value that feels "right" with the chosen aspect ratio from these other games.

I like to play R6: Siege at at 3:2 1920x1080p at 85 FOV. The calculator then says that this FOV choice is 85 vert. & 107.925 horz. However, for most games you'll be playing at 16:9 aspect. This means you're now forced to keep your fov consistent vertically or horizontally. You can either make the game you're converting to synced vertically, so 85 vert. & 116.9112 horz, or you can make the game you're converting to synced horizontally, so 75.42 vert. & 107.926 horizontally.

In other words, something has to give. You will need to trade one option for the other.

My dilemma is trying to battle the ethics of keeping one consistent over the other. Is it better to match horz. fov so that you can flick left and right properly? Or should you maintain vert. fov so you can get used to pulling the mouse down to compensate for recoil appropriately? What about taking an average of these two FOV values, so that the deviation vertically and horizontally is as low as possible for all points simultaneously?

Any links or discussion is welcomed. I prefer to use Monitor Distance 0% for tracking, but this isn't a post about sensitivity calculations it's about fov matching between games during the special case of matching a non-native aspect to a native aspect.

If you want to maintain focal length (0%) scale on both axes when using a stretched resolution you can just use a different vertical sensitivity.

if you play 4:3 stretched on a 16:9 screen, then the horizontal tracking sensitivity is faster within screen space by the ratio of “stretch” (in this case 1.333). So you’d just increase the vertical sensitivity by that ratio to compensate.

If a game doesn’t have the option and your mouse driver doesn’t either, you can use Rawaccel to do this without issue.