I am building a competitive team for vgc and want to know if tapu fini's misty terrain protects from taunt as well.
Generation VI Misty Terrain creates terrain that envelops the field and replaces the background environment and any other terrain that is already in effect. The terrain fades after five turns. This terrain has the following effects on Pokémon that are on the ground and not in the semi-invulnerable turn of a move. It prevents affected Pokémon from being afflicted by non-volatile status conditions or Yawn.
Source
As Taunt does not fall under non-volatile status, your Pokemon will be affected by Taunt.