To mitigate the hot weather of Seville, you can live in one of the smaller towns closer to the beach. If you don't want to be around of a bunch of Americans, avoid Rota and El Puerto de Santa Maria as there is a U.S. Naval Base there. This could be a plus though as it may help you make friends quickly if you don't speak Spanish. If you have any questions about that particular area, let me know. I lived there for 3 years about 10 years ago while I was in the Navy.
I add that remote work shouldn't be a problem for most EU. All Spain except Canary Islands are in the same time region than Germany so you would cover most Europe in real time (From Norway to Italy and from Spain to Croatia). One hour more than London or Lisbon.
