Yes. It is also a behavior.
"Powerful" is typically more of a descriptor or attribute rather than a standalone character trait. Character traits such as determination, compassion, or honesty are more foundational aspects of one's personality or behavior. The term "powerful" is often used to describe someone's influence, strength, or impact.
A character trait is basically the personality of someone. For example my character trait can be generous.
Yes, any personality trait is a character trait.
No it isn't a character trait.
no. special is not a character trait. you can say that the character is special.
Yes, insecurity is a character trait, if not a character defect.
Yes, isolated can be a character trait.
Yes, it may be a character trait.
Yes, it is a character trait.
A hummingbird does not specifically have one protective trait, but the way it can avoid predators is through its speed and small size. They are very agile.
Yes, hopeful is a character trait.
Impulsiveness is not a character trait. Being impulsive would be classified as a personality trait.