Got #1 Power aya to lv 100, it goes smooth even without the extra 11 EVs into spread attack for rush attack.
I noticed a little flaw with Greenmittenz EV spread. 55 speed EVs is just enought to outspeed Yuki's speed futo, the main threat, however with 350 points of speed, Mai's Speed remilia outspeeds power aya. A total of 58 Speed EVs are needed.
Is not an important problem, as the only remotely way it could kill Power aya, is doing a critical hit with inferno and leaving burn.
However, it still damages Power aya, and you will need to use a paste of the fog for healing it, or Yumemi's Power Kokoro will kill it with Arclight.
I've been some calcs with the excel puppetdex with Shinki team, and Power Aya can't solo shinki.
With art of combat, would need 2 moves to kill power mima, there is a small chance that a single twister will do, but you would need to get crits or max damage. Mima will attack, will not kill Power aya, but will leave it crippled.
The watatsukis are no problem, rush attack and spark javelin.
Defense Yukari is the main problem. With art of combat, there is even a small chance that 2 twisters are not enough. If you go with art of combat, you will have already lost a chunk of HP with mima. If you go with straw dolls, Mima will die with a single twister, however when you face yukari, you will already lost some health with straw dolls killing the previus puppets. When yukari attacks, you will have 60%HP remaining, enought to die with inferno, since gravity blast won't be a viable move from the AI, with the lowered HP.
I'm a bit confused with the damage calculator, as is like is ignoring Catasthrope stab. Also, art of combat seems to only boost Twister, regardless of type matchups.
Assuming you somehow managed to survive, you need to lose other 10% more of HP with straw dolls. Aya can kill Sariel without problem.
Asuming now that yukari missed inferno instead of using other move, and you could kill the rest of the stuff, you are with Power shinki now. Same case that with yukari, you can't one shot it. assuming that the map viewer is right and the devs put 64 EVs on EVERYTHING on Power shinki.
Conclussion: 64Fo.Atk and 58Speed, moves as Greenmittenz said, warp back to makai after defeating yumeko.