Download Universal Recoil Reducer First-Person Shooters Apex Legends
You can view the comparison videos below.
Without Universal Recoil Reducer
With Universal Recoil Reducer
You can adjust the interval between shakes
You can also adjust the X and Y shake to control where you want your mouse shake to go
In order to make it work, you need to Hold Both LEFT and RIGHT Mouse Button.
Not sure but maybe its also based on your sensitivity, I have enabled Mouse Acceleration
My Sensitivity is 1.5 and ADS Sensitivity is 0.8
And inside the tool my Interval is 20, X is 8 and Y is 6.
You should try in Firing Range to test which setting is best for you.