Dusknoir

With mediocre stats both offensively and defensively, as well as a suboptimal movepool, unfortunately Dusknoir will be only worth the Pokedex entry. It’s at least kind of bulky and resistant to Machamp.

Best PvE Offensive Moveset

• Hex marginally beats Astonish.

• Shadow Ball is the best Charge move available, but is limited to Community Day events and Elite TMs. 

• Ominous Wind’s STAB is compensated by Dark Pulse’s better parameters.

• Psychic has no offensive use on Dusknoir.

Best PvE Defensive Moveset

• Hex is again the better fast move.

• Psychic is a great option with good power and 2 bars, but it leaves Dusknoir easily picked off by Dark-type attackers. 

• Ominous Wind can be used frequently with 3 bars, but Dark Pulse is stronger and harder to dodge.

• Shadow Ball is the slower and harder-hitting option, and isn't a bad choice considering its limited availability. 

Hex charges fairly well, but it's a middling move overall. Astonish is yet another middling option

Ominous Wind is not a strong move, but it does have a small chance of granting a stat-boost on use, and its cheaper energy cost is more appealing for baiting shields. Psychic is an alright move and threatens Fighting- and Poison-type Pokemon. However, it doesn't do much against Dusknoir's counters. Shadow Ball is the strongest Charge Move available following the Duskull Community Day event, gets STAB, and is overall a solid move.  Dark Pulse has a coverage profile that is so close to Ghost that it may as well be a mono-Ghost set, however without STAB its damage output is less appealing and overall not viable.