Bewear is good but not spectacular in-game. Its high HP and acceptable Defense coupled with Fluffy make it a passable physical tank, while its robust Attack and Fighting STAB let it deal more damage than it takes. Its low Special Defense means it will crumble to most Psychic and Fairy moves, and its 60 Speed means it often takes hits before retaliating.
One of Bewear's Abilities is Klutz, an often worse-than-useless trait that prevents item use in battle. Fluffy is much better, elevating Bewear's walling capacity (provided you keep Bewear away from Fire moves). Always try to catch a Stufful with Fluffy instead of Klutz.
If you want to use Bewear in-game, a good moveset would probably look like:
Bewear
Ability: Fluffy
- Return (Malie City)
- Brick Break (TM in Verdant Cavern)
- Shadow Claw (Konikoni City TM Shop)
- Rock Slide (Melemele Sea with Sharpedo Jet)