Items: I don't understand why you gave everyone a Gem. Leavanny & Leafeon can benefit with Life Orb instead, Breloom maybe Focus Sash or Toxic Orb + Toxic Heal, Tropius a Harvest Sitrus Berry stall, and Hoppip... it shouldn't even be there. If Sceptile is holding a gem, it would benefit more by having Unburden as its ability.
Leavanny has a base 103 attack and access to Swords Dance, while only a base 70 sp. atk and no access to Nasty Plot. I think it's pretty clear that Leavanny should be a physical sweeper. False Swipe is also a move that never KO's your opponent, meaning it's a near useless competitive move.
Sorry, how is Leafeon a Mixed Sweeper? It only has one physical attacking move. Also, giving a Sweeper a 55% accurate move (Grasswhistle) is just asking for your opponent to have a free turn to set up on you/ KO you. Leaf Guard is also a useless ability. Use Chlorophyll instead.
Giving a 'wall' Solar Power is such a bad idea. If you face a Mono Fire team, you will almost undoubtedly face Ninetales, meaning Solar Power will sap 1/18 of your health each turn. Tropius also can't wall because of its poor typing.
Why are you using Hoppip? Why aren't you using Jumpluff if you want a scout? I can't see any form of gimmick that could benefit you using Hoppip in any way. Currently it's just on your team to faint.
So you gave Breloom Technician and no moves that made use of Technician. Mind Reader also only works with moves that don't take a turn to charge, which means if you're hit during the charge turn of Focus Punch, you'll flinch and it won't hit.
2 of Sceptile's moves are all too weak to make use of its attack. If you really wanted its speed to be higher, use Unburden Sceptile instead of Agility and give it a Gem so its speed will double when the gem is used. Sceptile also has a really good physical movepool (Acrobatics, Leaf Blade, Earthquake, Rock Slide, Drain Punch), along with Swords Dance to boost its attack. You really shouldn't be using moves like Quick Attack in competitive.
Essentially, your team are all weak to Poison, Fire, Flying and Ice. Breloom and Tropius are x1 against Bug because of their typing, but you have 2 quadruple weaknesses to Flying and Fire (Leavanny & Breloom, Hoppip (of all things) & Tropius).
I would make suggestions for team replacements, but I would reorganise your team to the extent of simply making you a new team, and that's not what RMT is about. I think you need to grasp competitive battling more thoroughly first.