While I do not know how to do it , it would be far easier to measure rotational inertia than it would be to calculate it. For instance, you could spin each wheel at the same speed and find out how much energy it takes to stop the wheel, twice the energy = twice the inertia. You could spin them on a wheel balancer and see how long they spin after you shut it off.

In order to calculate the difference, you would have to know the weight of the wheel/tire assembly at many different distances from the center. You might be able to calculate the difference if the wheels/tires were identical but different size, or different weights.

For instance, any weight at the outer edge of the wheel has far more inertia than the same weight near the center of the wheel.

I do not understand what you could use this information for.

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96 855R, 95 855,854, 90 744 Ti - 325,000 miles driven