porygon2 is pretty damn good; even though porygon-z has higher special attack, porygon2's higher defense makes it a good eviolite Pokemon.
Porygon2
Item: Eviolite
Nature: Modest/Calm
IVs: 0 Attack, 0 Speed (0sp is optional if you want to have the analytic ability)
EVs: 252 Special Defense/248 HP/8 Special Attack
ability: Analytic (download is ok too, but I prefer analytic since its speed isnt too good and download has a risk of boosting the attack stat. trace is ok, but as I said before, I think analytic is a little better)
~~~~
Moveset:
Pain Split [gain hp whilst doing damage]
Tri-Attack [stab, and its one of the few god-forsaken special Normal type moves that don't alternate type, not counting type-changing abilities like Pixilate or aren't exclusive moves to certain Pokemon lol]
Psychic [deal with fighting-types, and also be able to attack ghost types with the normal-type immunity]
Recover [just for hp recovery in case pain split isnt usable at that moment]
~~~~
thankfully porygon2 is a normal type so I can just use up one move for weakness coverage, only problem is dealing with steel types, but pain split can help out a little in regards to that. good part is that psychic is an awesome move in general and it deals with its only weakness. hopefully this is decent moveset, its helped me out of plenty of situations in battle.