Change the Bend properties of the Reference. A Reference will behave the same as the Instance with a difference. Notice the thick grey line above all modifiers. That line is a delimiter: everything below the line is mirrored to the Master object and vice-versa. Any modifier above the line is not mirrored.
Add a Taper modifier above the grey line and play with its parameters. Note that the other objects don't have the new Taper modifier applied to them. Also notice the Taper modifier is not bolded.
Add a Twist modifier below the thick grey line and change some parameters. Now all objects Twist according to these parameters!
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