Comment by MarioMan

It should be. Look at DraStic, for instance, a DS emulator which runs ARM code on Android. It's a fairly performant and accurate emulation option. https://play.google.com/store/apps/details?id=com.dsemu.dras...

Now if you're talking about trying to run one of these emulators on an ARM build of Linux, you wouldn't see these performance improvements since their designs are optimized around x86 CPUs, not ARM.

Edit: Several far more informed comments than mine have mentioned that running on ARM is only one small piece of the performance coming from DraStic.