I would like to ask a shallo in hilchos tznius, my wife is covering her head with a "Shpitzl" and scarf but at home she has a wig that she wears only in front of me, Now here’s the question, when she’s a Nida the husband is not allowed to see her hair, as its considered Ervah, is wearing a wig considered covering her hair or it's counted as seeing her own hair?

Shalom Covering one's hair with a wig is considered a hair covering and is permitted before her husband when she is niddah. Kol tuv