It would be great to be able to change your variant of the mob you are such as axolotls you can only be the pink one and not any of the others

It is possible in the game! After getting the identity, if you get yellow, click the axolotl option again to get different color!

Can anyone else confirm this? . I could not switch to a variant by selecting the axolotl option again even after killing all types of axolotl.