How are your writing skills?
The interviewer is interested in how experienced you are as a writer beyond translation exclusively. Some translations, particularly in literature, require an elevated and refined skill set in writing. Review the job description in detail for any indication that the position requires a specific writing style or skill level, and be prepared to reference specific examples of your work that support what they want to see.
"I have extensive writing experience in several capacities, primarily academic writing, articles, and blog posts. I am most familiar with MLA, Chicago, and APA styles. I'm a bit of a perfectionist and have particularly keen attention to detail, so my editing skills are equally strong."