From Pluralpedia, the collaborative plurality dictionary
verbalflux (adj.)
Applies toheadmates

Verbalflux is term used to describe people who fluctuate between full-verbal, semi-verbal, limited-verbal, and non-verbal. They can have any verbal state at any given time, and they don't have to fluctuate between all forms of verbality.

The shortened form VF can be used in conjunction with others, i.e. "VF-NV", which denotes that the person is verbalflux and currently non-verbal.