First off, they provide you a homemade guidebook that is simply fantastic. It includes an English version. The recommended tapas places were excellent and affordable (we're not high rollers). Plus, it recommended other interesting attractions. This was the best local info I've been provided by any host on airbnb.
Ana doesn't speak English (I speak a tiny amount), but with the Google Translate app we had zero problems. She is super nice and hospitable. If you message the hosts via airbnb, you'll get responses from their partners in near-perfect English, so it's easy to set up any logistics beforehand.
If you want a local Sevilla experience, this is a great option.