PPSSPP (PSP emulator for android) got a major update recently! Huge speed increase, better compatibility. And its completely FREE and Open Source! : r/Android
Octopus - Gamepad, Keymapper 3.0.1 (arm-v7a) APK Download by Octopus Gaming Studio - APKMirror
Panda Gamepad Pro MOD APK v1.4.9 (Many Feature) - Apkmody