Galarian Stunfisk

Galarian Stunfisk got a lot of hype and popularity upon its release into Pokemon Go.......but for PvP. Unfortunately it lacks stats to be viable on the PvE side, with pitiful offensive stats and movesets that leave more to be desired. It's not too terrible for gym defense though, but having a weakness to Fighting-types usually isn't favorable when many of the best defenders share the same vulnerability. 

Best PvE Offensive Moveset

• Metal Claw performs better on offense, but should be paired with Flash Cannon due to shared typing. 
• Mud Shot and Earthquake pair well together to fulfill a Ground-type role. 
• Muddy Water is a PvP move.
• Rock Slide is a good move, but lacks STAB. 

Best PvE Defensive Moveset

• Metal Claw has a higher base power, making it more preferable for defense. 
• Muddy Water doesn't threaten a lot of damage, but is the most spammable being a 3-bar move, in addition to being the hardest to dodge. 
• Rock Slide is quite decent being a 2-bar move with respectable damage output, but lacks STAB. 
• Flash Cannon benefits from STAB, but being a 1-bar move means it can't be used as frequently. 
• Earthquake is the worst option available for defense due to how slow it is, not to mention being a 1-bar move. 

Mud Shot is recommended for its excellent energy generation, which is needed for Galarian Stunfisk's costly charge moves.

Rock Slide provide valuable coverage against common typings, in addition to costing less energy to bait shields. Earthquake benefits from STAB to deal significant damage, though it costs a lot of energy to use. Flash Cannon also benefits from STAB, but its coverage is not relevant for most formats.