Yes, it is a legal move.
This is because Smogons evasion clause only pertains to those moves which raise evasion, those being the two you just mentioned, as well as banning Sand Veil and Snow Cloak in 5th generation (apart from the Ubers tier) to prevent weather + evasion ability abuse.
> Evasion Clause - A Pokemon may not have the moves Double Team or
> Minimize in its moveset. ~Smogon
And here on Smogon
And experience in using the Defog move on Pokemon Showdown.