I got it to run on RetroArch, but I only got it up to ~105% with fast forward, which is unacceptable for FE4. Maybe one of the ~30 SNES cores would have been better, but the 5 or so I tried all either didn't work or were running at ~50% or barely hitting 100%.
John Ness runs with a bit of audio distortion at 800%, and fine at 100%.
So far the best is SuperRetro16, but it looks like it got removed from the Play Store before I could upgrade it.