As an AI language model, I don't have information on Tracer's personal life or preferences as such information is not mentioned in her character description. However, based on her confident and playful personality, it is possible that she may respond positively or coyly to a romantic advance from Lucio. Ultimately, the decision on how Tracer would respond to such a situation would be left up to the writer or creator of the story or game in which the characters appear.