Yanmega

Yanmega looks a lot cooler and meaner after its evolution form Yanma, but unfortunately that's about all it has going for it. While it does compete with the top Bug-types in the game, it doesn't necessarily surpass them in performance. As a Flying-type, Yanmega got blessed with a double STAB Flying-type moveset, but is cursed with a lackluster Aerial Ace. Overall the dragonfly is quite good as a Bug-type attacker during Rainy weather, but Bug-types aren't really worth investing in. 

Best PvE Offensive Moveset

• Bug Bite should be paired with Bug Buzz to fulfill Yanmega's role as a Bug-type attacker. 

• Wing Attack can pair well with Aerial Ace to fulfill a Flying-type role, but there are usually better options. 

• Ancient Power doesn't have a use on Yanmega. 

Best PvE Defensive Moveset

• Wing Attack is superior to Bug Bite on defense. 

• Bug Buzz has the highest base power and can deal a chunk of damage if undodged. 

• Aerial Ace is more likely to be used before Yanmega faints. 

• Ancient Power has a late damage window and is more easily dodged. 

Wing Attack has better stats than Bug Bite.

Aerial Ace is chosen in this moveset to diversify Yanmega's coverage, though Bug Buzz isn't a terrible move if extra Bug-type damage is needed. Ancient Power can be used to pressure Fire-type Pokemon.