Fire signs: Sagittarius
Sagittarius is the odd one out because they tend to be less competitive and doesn’t worry about being number one unlike Aries and Leo. They also tend to be less possessive than the rest of the fire signs. Plus they are the only fire sign that is half human/half horse while the rest are straight up animals.
Earth signs: Virgo
Virgo is the odd one out because they tend to care about materialism less unlike Taurus and Capricorn. They also tend to analyze and stay in their heads more than the other Earth signs. Also if you can convince a Virgo about something they can easily change their minds unlike Taurus and Capricorn. Plus they are the only Earth sign that is represented by a human while the rest who are animals.
Air signs: Aquarius
Aquarius is the odd one out because they tend to like to be alone and enjoy their own company unlike Gemini and Libra. They also tend to be less superficial and gossipy than the other Air signs. Also, sometimes they can come across as so stubborn in their beliefs and sometimes introverted which is not an Air sign trait.
Water signs: Scorpio
Scorpio is the odd one out because they tend to keep their emotions to themselves (even though they are emotional) and don’t like to wear their heart on their sleeves unlike Cancer and Pisces. They also tend to be aggressive and like power more than the other water signs. Can also have a mean streak more than Cancer and Pisces who are known to be innocent and nice. Plus they are the only water sign that is represented by an insect while the others are represented by sea creatures.