Welp, Sabeleye has Prankster ability, which gives non-atk moves +1 priority and its the only poke which can learn a pool of status moves like taunt,twave,toxic,willo-wisp.. which makes it way better than its mega. And mega sab's a wall.
I'd choose Normal Sab over mega.
And that's a nice team over there ric :y:
and about this sab of yours:
LEAD: Sableye (Calm)
Recover
Will-O-Wisp
Taunt
Foul Play - Night Shade
I'd say Knockoff rather than nightshade, so while facing tanks such as bliss or something else you can taunt- knockoff-wisp/toxic item and kill it.