Realistically, I think Play! is the only emulator around. Compatibility isn't at the state of having much of anything playable, as far as I know. A well-optimized PS2 emulator could eventually be playable on a Shield TV, but to be honest, even Dolphin took a lot of talented developers and a lot of free time to get to where it is; I'm not seeing Play! having nearly the same development activity, and I think PCSX2 would need a lot of work for non-x86 systems.