Nidoqueen

Nidoqueen is the defensive half of the Nido-royalty. Unfortunately, Nidoqueen’s stats aren’t very defensive, and weaknesses to the common Psychic and Water types only hurt. There’s little point to using Nidoqueen on offense when Nidoking has the same optimal movesets and 24 more points of Atk.

Best PvE Offensive Moveset

• Poison Jab pairs with Sludge Wave for a STAB Poison moveset. Poison Sting falls behind.

• Mud Slap and Earth Power is the way to go for Ground coverage.

• Earthquake, Stone Edge, Poison Fang.... all basically useless for Nidoqueen as-is.

Best PvE Defensive Moveset

• Mud Slap and Poison Fang is generally the way to go for defense, as Mud Slap has great defensive performance and Poison Fang comes out frequently. However, Poison Fang is also pretty weak.
• Poison Jab and Earth Power is another decent option. Poison Jab is weaker and Earth Power comes out less frequently, but the latter at least poses a threat in terms of actual damage output.
• Poison Sting and Bite are sub-par defensive Fast Moves.
• Earthquake, Sludge Wave, and Stone Edge take too long to launch, and Nidoqueen will likely be down before launching them.

Poison Sting has incredible energy generation while still maintaining decent damage. Poison Jab's higher damage output is a viable alternative, immediately synergizing with Poison Fang's DEF drop. Bite deals strong Dark-type damage, but lacks STAB and energy gains. 

Poison Fang is all but mandatory on Nidoqueen, functioning as both a strong bait move and a powerful spammy option in its own right. Earth Power helps Nidoqueen access a Ground-type charge move sooner, while Stone Edge provides wide coverage. Since both Earth Power and Stone Edge cost the same energy, Nidoqueen doesn't need to shield bait. Sludge Wave or Earthquake could be chosen as harder-hitting options, but the cost of 10 more energy risks Nidoqueen fainting before being able to use them.