Its engine specific or rather movement specific. That said it took me literally a year of fine tuning to get to the perfect sens in Overwatch. Basically, you think about the distance you would most likely be from your target eg. in Overwatch likely 20-25M and stand at that distance from a spot on the wall. Then you adad strafe keep trying to literally keep your crosshair on the dot as good as possible. After intensive trail and error you will find it. The criteria for the perfect sensitivity is one which does not 'shiver' eg bounce left and right of the target dot. A good sens is one that lets you focus on the dot on the wall and allows you to keep the crosshair on the dot PEFECTLY with no trembling and also one that you don't need to grip your mouse tightly in order to use it(happens when sens is too high). It will take fucking ages but you will find it. Overshoot or undershoot of the crosshair is deceptive in the fact that your mind sometimes compensates for high sens by delaying your tracking, so a exceedingly high sensitivity can sometimes look too slow when you track. Same for low sens except your mind will compensate by overshooting. You just gotta try a lot of sensitivities to find the right one. It will be frustrating af.
This method allows you to find a sens that allows you perfect control when moving and strafing and also perfect tracking relative to the movement speed of the character models of the engine eg. The Overwatch engine. For reference, my perfect sens is 800 DPI @ 4.35 Ingame which is 39.81CM/360 (I play in mid masters)
I have yet to find my sens in csgo, however. I imagine it will take less time now that I know what to look for. Your sens will almost always be different on different game engines and different character models. Overwatch is lenient in that its hitboxes are quite large, compared to a game like csgo, which need pixel perfect precisiom, so 50+cm/360 is not uncommon for that.
Higher sens: Faster but less accurate response. Good for projectiles
Lower sens: Slower turns and responses but more accurate. Hitscan
I like to think that the perfect sens is a balance/compromise of fast turn and good precision. Despite what I said about 'perfect sensitivities' there is probably a small range of sensitivities that you can use, that you would perform well in.