This is very late, but I’ve been meaning to do this rate for a while. You’ve got a pretty decent team, but I’m not entirely sure how you managed to win a tournament. Some of your Pokemon aren’t too viable, and the ones that are have less-than-optimal sets. So without further ado:
Mudbray
Mudbray is a pretty decent Stealth Rock setter, but it’s outclassed by Pawniard (more on that later), and it just doesn’t have enough defensive presence to be too useful. Special attackers like Staryu and Porygon take advantage of it easily, and even physical attackers like Grookey are able to OHKO Eviolite Mudbray, as shown with the calculation below:
236 Atk Life Orb Grookey Grassy Glide vs. 116 HP / 40 Def Eviolite Mudbray in Grassy Terrain: 18-26 (72 - 104%) -- 6.3% chance to OHKO
Looking at the rest of the team, you really need a Grookey counter. So how about replacing Mudbray with Foongus or Koffing? Both resist Grookey’s most common moves (barring Knock Off, and Foongus must beware the rare Acrobatics), and can hit it super effectively in return, plus provide more helpful utility. Foongus allows you to use the amazing Spore, plus it’s also a nice check to Spritzee, Timburr, Onix, and more. Koffing is also good against Grookey, Spritzee, and Timburr, plus it has a better defensive typing, and it can threaten physical attackers with Will-O-Wisp. I recommend Koffing, but you can decide for yourself which your team needs more.
Foongus @ Eviolite
Level: 5
Ability: Regenerator
EVs: 124 HP / 156 Def / 156 SpD
Bold Nature
- Spore
- Giga Drain
- Sludge Bomb
- Synthesis
Koffing similarly checks Grookey, Spritzee and Mareanie, but its coverage also allows it to score a KO on Ferroseed. It exchanges putting opponents to sleep with burning them, which can be more helpful depending on the matchup.
Koffing @ Eviolite
Level: 5
Ability: Neutralizing Gas
EVs: 36 HP / 196 SpA / 236 Spe
Timid Nature
- Sludge Bomb
- Will-O-Wisp
- Fire Blast
- Thunderbolt
Timburr
Defog is okay, but you really should be using Knock Off to put a dent in the defensive terrors that are Vullaby, Ferroseed, and Mareanie (plus Berry Juice users, Life Orb users, etc… LC is very item-based.). Defog is a decent option, but it probably won’t be as helpful as Knock Off, due to the sheer utility the latter has.
Timburr @ Eviolite
Ability: Iron Fist
EVs: 196 Atk / 156 Def / 156 SpD
Adamant Nature
- Drain Punch
- Mach Punch
- Thunder Punch
- Knock Off
Darumaka-Galar
Not a good choice, don’t use it. Sure, the high Attack stat may look appealing, but Darumaka absolutely must have a Choice Scarf to succeed. Hustle puts a damper on its effectiveness, it’s weak to Stealth Rock, and it takes a large amount of damage from Timburr’s Mach Punch and the like.
196+ Atk Iron Fist Timburr Mach Punch vs. 36 HP / 76 Def Darumaka-Galar: 14-20 (58.3 - 83.3%) -- guaranteed 2HKO
See? Not good at all. Ice types as a whole aren’t very good in LC, so I’d recommend a different powerful attacker: Diglett. It’s an excellent way to deal with Mareanie (or at least assist, due to Mareanie’s Scald taking a chunk out of it), and it can trap other Pokemon with Arena Trap -- plus it has priority and a blazingly fast Speed stat to revenge kill.
Diglett @ Eviolite
Level: 5
Ability: Arena Trap
EVs: 116 HP / 156 Atk / 236 Spe
Jolly Nature
- Earthquake
- Final Gambit
- Beat Up
- Earth Power / Sucker Punch
It might seem like an odd set, but it works, according to Smogon. Beat Up helps out against Abra when all your Pokemon are still healthy, Earthquake is basic STAB, Final Gambit lets you sacrifice Diglett for something like Mareanie or Vullaby, Earth Power lets you do damage to Onix without Weak Armor taking effect (plus it works effectively even in Grassy Terrain or after Diglett is burned), and Sucker Punch is simply priority.
Archen
Good set, honestly. I don’t have any complaints here, but you could opt for Heavy-Duty Boots over Berry Juice if you feel Stealth Rock poses more of a problem and can get you into Defeatist range earlier.
Archen @ Berry Juice / Heavy-Duty Boots
Ability: Defeatist
EVs: 50 HP / 180 Atk / 6 SpA / 196 Spe
Jolly Nature
- Stone Edge
- Dual Wingbeat
- Heat Wave
- Aqua Tail
Pawniard
Pawniard should be your Stealth Rock setter, not Mudbray. It’s generally bulkier and better overall, but you will need to watch out for Fighting types. I would replace Swords Dance with Stealth Rock, as Pawniard still has plenty of power without the Attack boost.
Pawniard @ Eviolite
Ability: Defiant
Level: 5
EVs: 156 Atk / 36 Def / 116 SpD / 196 Spe
Jolly Nature
- Knock Off
- Iron Head
- Sucker Punch
- Stealth Rock
Grookey
Leech Seed is not a good move at all. Grookey needs to hit hard and hit fast, and Leech Seed just doesn’t cut it. Use Knock Off or Swords Dance instead to be even more of a monster on the field, or even Fake Out for a bit of chip damage that helps in revenge killing opponents.
Grookey @ Life Orb
Level: 5
Ability: Grassy Surge
EVs: 236 Atk / 36 Def / 236 Spe
Jolly Nature
- Knock Off / Swords Dance / Fake Out
- Grassy Glide
- Drain Punch
- U-turn
Overall, your team is pretty solid. There are a few Pokemon I’d advise replacing (Mudbray, Darumaka-Galar), but you’re strong both offensively and defensively, making for a well-rounded team. I hope the improvements I’ve suggested work well for you, and best of luck in LC!
Importable team here (with Koffing, not Foongus)