The sentence "Lucy is a saxophonist, gifted possibly without equal, is that of a master because of her skill at it very sought after." is not grammatically correct or clearly structured, making it difficult to understand. It appears that you are trying to say that Lucy is an extremely talented saxophonist, potentially unmatched in her abilities, and is considered a master due to her skill, which makes her highly sought after.
Here's a revised version of the sentence that is clearer and more grammatically correct:
"Lucy is an exceptionally gifted saxophonist, possibly without equal. Her mastery and skill make her highly sought after."