Nah, Hidden Power Fire would definitely be superior to Fighting on the Espeon set. What are you trying to hit with Fighting, anyways? If the answer is Tyranitar, Grass Knot does almost as much anyways, and against Chople variants you'll be glad you have it instead of HP Fighting. Grass Knot also helps a ton against SDef Hippowdon, Gastrodon, Jellicent, etc. Besides, Espeon desperately needs HP Fire, both to OHKO Scizor and OHKO Genesect as it switches in. It's also nice against Forretress, Skarmory, and Jirachi, all of which would flat-out wall CM Espeon if it lacked HP Fire. Espy definitely suffers from four-moveslot syndrome, and no set is perfect by any means, I'm just trying to maximize its overall usefulness.