A shooting star can be a green candlestick, though a red one signals stronger bearish conviction. The color of the candle is less important than its overall structure; while red candles often indicate stronger bearish momentum, a green candle can still qualify as a shooting star if the upper shadow is at least twice the length of the body.
A red shooting star indicates a more potent reversal than the green version because price closed lower than the opening price during the session.
The structure matters more than the color.