Suppose there are two 2-d multivariate normal distributions , as in the image below:
There is no correlation between the x and y components in the distributions, and the variance for each dimension is the same.
Is it correct to say that the angle between the two distributions could be expressed as a wrapped normal distribution, with $\mu _{\theta } = atan2(\mu_{2_y} - \mu_{1_y}, \mu_{2_x} - \mu_{1_x})$?
If so, I am not sure how to derive the variance of this wrapped distribution, based on the two multivariate normal distributions. Intuitively, the variance of the wrapped distribution should decrease as the distance between $\mu_1$ and $\mu_2$ increases. Also, the variance should increase as $\sigma^2_1$ and $\sigma^2_2$ increase.
How can I derive the variance and the standard deviation for the wrapped distribution of the angle between the two distributions?