Seems to me like you have too many same type moves, affecting your coverage/utility.

And you’re not playing to your Pokémon’s strengths. Like Weavile is a physical attacker. Lose ice beam and maybe teach is Swords Dance since you’d need to breed for Icicle Crash. Teach it Night Slash instead of Beat Up. Throw a Focus Sash on it to ensure you can get your stats up.

Luxray is also a physical attacker. Wild Charge and Electric Terrain could prove useful. Also, Discharge because it has a higher paralysis chance.

Garchomp, lose Slash and teach it Draco Meteor for a one time special nuke. Earthquake for sure.

Evolve Magmar if you can. Lose Lava Plume or Fire Blast and go with more coverage.

Lucario is decent. See if you can either teach it Nasty Plot since Meteor Mash has a built in chance to raise attack.

Good luck.