Thievul @ Thievul CrestAbility: StakeoutEVs: 252 HP / 252 DEF / 4 SPDImplish Nature (Could have a -SPD nature to make sure that your Sweeper go on the field harmless)-Knock Off-Nasty Plot-Parting Shot-Baton Pass
I believe that with the crest's innate +1 SPA and -1 SPA upon switch in, Thievul is better as a Baton Passer aiming to pass 3 SPA buff to your fast Sweepers, by investing in max DEF and HP with the -1 SPA to opponent. Knock Off provides utility.