By definition, forefoot varus is an pathomechanical entity in which the plantar plane of the forefoot is inverted relative to a perpendicular bisection of the rear of the calcaneus when the subtalar joint is in its defined neutral position and the lateral column of the forefoot is loaded to maximally pronate the midtarsal joint. This theoretical construct was first clearly elucidated by Dr Merton Root, DPM.
The rearfoot has to pronate to bring the medial side of the forefoot to the ground. By definition this is a fixed osseous or bony deformity, so nothing can be done to “fix” it. Forefoot varus is not common, probably only making up 1-2% of the pathomechanical entities of the forefoot. It is often confused with forefoot supinatus (which is soft tissue and can generally be “fixed”).
There is so much misunderstanding about forefoot varus and so many who have no clue what it really is and pretend to speak with some sort of authority on it. Please be careful when reading about it and debunk the nonsense whenever you can.