This is the update you all have been waiting for. The Wild Dogs now can breed with each other and pass traits from any of the wolves to the fox or fox to any of the wolves.
The 2.6.2 update does have the Fox tail shape in the Wolves so you will want to make sure to update them as well as having the wolf tail shapes in the fox. In order to make sure the right natural tail got to the right animal the tail shapes had to get a name adjustment if you have a Natural tail in the Wolves it is now called Flair and if you have a Natural tail in the Fox it is now called Fox. The size of the tail will have the Flair or Fox in front of the size.
The furs will not pass among the species they are species specific.
A hybrid is in the plan for a future update but the shape is still under development.