I heard that Besamim is NOT used for Havdala on Motzei Shabat Chol Hamoed, is this true?
Both opinions are mentioned. I personally use besamim. On Motzei Shabbat which is yom tov, no besamim are used since the bessamim "revive " us from the shock of losing our elevated status (neshama yetara), but the joy of yom tov makes this unnecessary. Chol Hamoed also has joy, but not to the same degree.