>>29833842>>29833878>>29834149Something to note is that the Memories aren't Plates. You don't get a 20% boost on Multi Attack. You're completely itemless, have poor stat distro (the worst of which is that you're fairly slow), no recovery options, have no utility outside of Parting Shot (which isn't enough to carry a mon: see Pangoro), no priority, and your only real set-up option is Swords Dance.
It's probably a solid UU on the sole point that it's a 570 BST Fairy type, but it's not going to make any sort of impact in OU.
>>29834067 was right that Movepool is more important than stats, but failed to notice that despite Silvally's enormous movepool, most of those moves are just raw attacking options that don't really contribute much to its viability.