Scizor

Scizor has okay-ish ATK and DEF stats, but is held back from true greatness by lackluster offensive typing, which relegates this Pokemon to a Psychic or Fairy-killer niche.

Defensively, Scizor's decent bulk and Steel-typing offer many resistances, but Fire is a common move type on many raid bosses, exploiting its glaring double weakness.

All-in-all, Scizor is not a great investment. Its Mega is an alright choice for a Bug attacker, though.

Best PvE Offensive Moveset

• Fury Cutter and X-Scissor offer the highest DPS when facing Psychic, Dark, and Grass-types
• Bullet Punch and Iron Head are the preferred set for dealing with Rock, Ice, and Fairy-types
• Night Slash is underwhelming; a three charge move with a longer cooldown and does not benefit from STAB, only offering additional Ghost coverage

Best PvE Defensive Moveset

• Bullet Punch is superior to Fury Cutter on defense.
• X-Scissor is clearly superior to Night Slash; both are three charge moves with similar DPS, but the latter's cooldown is significantly longer, making it easier to take advantage of dodge windows.
• Iron Head is often better than Night Slash, offering higher DPS at a shorter cooldown despite being a two-bar charge move, although the latter offers wider type coverage.

Bullet Punch tends to be preferred over Fury Cutter for its higher damage output, as Scizor's Charged Attacks aren't particularly impressive to be worth the increased energy gain. They're also mostly cheap enough anyways. 

Night Slash is Scizor's cheapest option and provides coverage against Steel-type Pokemon. X-Scissor is a wonderful STAB move, though Bug is often questionable offensively. Trailblaze smacks Water-type Pokemon and provides an Attack boost. Iron Head is often redundant with Bullet Punch's damage output. Return is far too expensive considering Scizor's frailty