Is it permissible in Islam to watch weekly horoscope videos on YouTube if the individual in the video is a Shia Muslim who speaks positively about the Ahlulbayt?
Strictly speaking, astrology in the premodern era was often considered a natural science, not a theology. Therefore, the religious orientation of an astrologer is irrelevant to whether or not one decides to listen to them (just like the religious orientation of a doctor is irrelevant to their capability as a physician).
Hadith and scholarly views about astrology among Shi'a have varied significantly historically.