egorek375

Fixed it for you now. You were a bit unlucky and saved those exactly during an update which made some data not save correctly.

It's slow when converting from high FOV to low FOV like from hipfire to scope.
But for hipfire to hipfire in your case you're going from low FOV (90) to high FOV (111.31), then it will be opposite.

There's arguments for both really. MDV will keep the "center" portion of your screen the same (so your aim in the middle will be the same), while MDH will extend out to the edges. Personally I prefer MDH because the horizontal axis is where you mostly move the mouse. 

You will have 10 more HFOV when going from 4:3 to 16:10. So, your sensitivity will feel slower ( at smaller degrees of movement ) if you keep it at 2.5. But a 360 turn will take the exact amount of distance on your pad.

Nah.
Only games that change the fov based on the user's aspect ratio will need to have their sensitivity recalculated. Check in the calculator what the actual fov values are. If the vertical remains the same, then the fov within the square aspect ratio was unchanged, and the sides were just cropped.
 
Why?
If you change your aspect ratio by reducing the horizontal length, and the opposite fov (vertical) changes, that means the game has zoomed in or out to preserve the horizontal fov. A change in zoom needs a new sensitivity value if you are using any fov based converison method (everything except 360 distance).

No problem.
Same FOV as in Hardline - 74. If you play with the same resolution, that is. 

13 Hardline 74 FOV
0.10/ 0.024752 Fortnite 80 FOV, If possible - change it to 100