It's important to understand that a profession can span different industries. For instance, in the legal profession, one can work in corporate, financial, or criminal law. The same goes for the profession of the editor. The framework of editing can be applied to many topics and industries.
First, fall back on the fundamental aspects of editing itself: demonstrate your expertise and mastery of the fundamentals by explaining techniques, methods, and frameworks that you've learned in your education or on the job. If possible, end by relating it to some common ground that you have found between your past work and the publication you're applying to.
In your response, make sure you address the main concern directly and inspire confidence by conveying that you have a strong understanding of the publication's content.