My ou team

I haven't thought much about the team and I kind of just throw random pokemon into it. Didn't battle much after the ladder score reset. I notice that I have two choice scarf users, I probably need to change it but don't know what I should change. My team is also weak to water type generally. So can you please help me edit my team?(Btw, I need better nickname)

i look dumb (Clefable) @ Leftovers  
Ability: Magic Guard  
EVs: 252 HP / 252 Def / 4 SpA  
Bold Nature  
- Moonblast  
- Soft-Boiled  
- Calm Mind  
- Flamethrower  

i ran (Heatran) @ Leftovers  
Ability: Flash Fire  
EVs: 252 HP / 252 SpA / 4 SpD  
Modest Nature  
- Flash Cannon  
- Lava Plume  
- Stealth Rock  
- Roar  

my meteor hurts (Latios) @ Life Orb  
Ability: Levitate  
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
- Draco Meteor  
- Psyshock  
- Thunderbolt  
- Surf  

my arms are floating (Hoopa-Unbound) @ Choice Scarf  
Ability: Magician  
EVs: 252 Atk / 4 SpA / 252 Spe  
Hasty Nature  
- Hyperspace Fury  
- Psychic  
- Energy Ball  
- Drain Punch  

I have armorKnightmare (Scizor-Mega) @ Scizorite  
Ability: Technician  
EVs: 248 HP / 252 Atk / 8 SpD  
Adamant Nature  
- Swords Dance  
- Roost  
- Bullet Punch  
- Bug Bite  

flying tiger (Landorus-Therian) @ Choice Scarf  
Ability: Intimidate  
EVs: 252 Atk / 4 SpD / 252 Spe  
Jolly Nature  
- Earthquake  
- U-turn  
- Stone Edge  
- Knock Off

Team looks good.

How about Knightmare for the Scizor?

sure
do u think I should change the item for hoopa-u, i am thinking assult vest

Yeah, assault vest would be a much better choice. Is Tyrantrum in OU? (Sorry xD). It would probably be better than Heatran as the Hazard Setter (use Stealth Rock, Dragon Tail, maybe substitute, Head Smash and/or attract.)

tyrantrum is RU. I need heatran to take willowisp, and to be honest, heatran is a way better hazard setter. It has way better defenseive typing and special bulk. I also need heatran for ferrothorn, scizor, and talonflame(rarely, they carry steel wing for rock types). I'll try assualt vest, though it makes me weaker to mega metagross.

try life orb hoopa as ur team has little for stall

also if the water weakness is rather crippling u could change mega scizor to mega venu and try this set

Venusaur @ Venusaurite
Ability: Chlorophyll
EVs: 232 HP / 252 SpA / 4 SpD / 20 Spe
Modest Nature
- Giga Drain
- Sludge Bomb
- Hidden Power [Fire]
- Synthesis

I need mega scissor for mega metagross and stuff though, and assault vest is for gengar. I am weak to stall though... And I am weak to gengar, tornadorus therain and azumarill

I changed my latios to rotom-wash to deal with water types slightly better and counter tornadorus-t