Dugtrio - Instead of Dugtrio as your lead, I would suggest Genesect. Either way, I have found that Focus Sash Dugtrio is great for revenge killing and trapping key opponents.
Dugtrio @ Focus Sash
Trait: Arena Trap
EVs: 4 HP / 252 Atk / 252 Spd
- Sucker Punch
- Stealth Rock/Stone Edge
This set is great for doing a an array of things, but taking down weather leads is it specialty. He can come in on a weakened Tyranitar or Abomasnow and KO with Reversal (Provided Duggy takesa hit first, and for Abomasnow you might wanna use Reversal right off the bat if you know it is running Ice Shard), or he can come in and KO Ninetales with Earthquake. Sucker Punch is rather unconventional on Dugtrio but it works like a charm and is crucial to the set by giving priority. The only flaw with being able to trap weather starters on this team is that you have no weather of your own to replace theirs with.
Genesect - Spot on :)
Scizor - Looks great, just change his EVs to 252 HP, 252 Atk, and 4 SDef.
Meinshao - Give him a Jolly Nature and run Stone Edge over Grass Knot.
Forretress - Sitrus Berry is a no-no, gice him Leftovers instead. If you put Stone Edge on Dugtrio, change his nature to Bold instead of Relaxed and switch Gyro Ball for Stealth Rock, but only if Dugtrio has Stone Edge, if Duggy has SR then keep it the way you have it.
Rotom-W - Looks good
Now, I only improved your sets, I did not change any pokemon. The team is not bad, however I can't help but notice the fact that 3 team members are hit 4X Super Effectively by Fire, and only one team member that resists it. This means that you are vastly threatened by pretty much any Fire type, and a sun team would have a hay-day with the team. If you would like me to help fix this issue please let me know.