Surprisingly, this is the first time I'm seeing a Charizard in Pokemon Database. Looking at it first glance, your team is not all that bad. Kommo-o doesn't get all that many uses, hence UU, and I can see minor improvements.
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Anat (Greninja-Ash) (f) @ Choice Scarf
Ability: Battle Bond
EVs: 252 Atk / 252 Spe / 4 HP
Jolly Nature
- Hydro Pump
- Dark Pulse
- Ice Beam
- Water Shuriken
Anat - "water spring" Semitic Goddess of fertility, hunting, and war worship
All I would say is that Greninja benefits most from a Scarf. It's strong, fast, and has a large pool to paddle in.
Eun-Ji (Landorus-Therian) @ Life Orb
Ability: Intimidate
EVs: 252 Atk / 252 Spe / 4 SpD
Adamant Nature
- Earthquake
- Rock Slide
- Knock Off
- U-Turn / Defog
Eun - "Mercy"
Ji - "Ground"
I know Kommo-o is very important because of it's Z-Crystal, but I'll get to that later. Lando-T and Greninja is the best core in OU, and for good reason. The resist the other's weakness and neither need stat boosts to be powerful, providing strong pivots.
Moab (Charizard) @ Charizardite X
Ability: Tough Claws
EVs: 252 Atk / 252 Spe / 4 Hp
Jolly Nature
- Dragon Dance
- Dragon Claw
- Flare Blitz
- Roost
I played MW3, and at 25 streaks, you could call in a Moab.
Charizard X’s typing is one of the most unique because it doesn’t have a weakness to water. Now it can core with Greninja, but that isn’t advised because this Zard is a set up sweeper.
Beonet(Serperior) @ Leftovers
Ability: Contrary
Shiny: Yes
EVs: 252 SpA / 252 Spe / 4 HP
Timid Nature
- Leaf Storm
- Hidden Power Fire
- Substitute
- Leech Seed
BEONET
composed of Old English beonet "bent grass"
Serperior is one of my favorite Pokémon. I started my first adventure in B2W2; Serperior was my first Pokémon. I then gradually got every other game and now competitively play Showdown!.
Hoshiko (Jirachi) @ Normalium Z
Ability: Serene Grace
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Lucky Chant
- Zen Headbutt
- Ice Punch
- Iron Head
Jirachi can be very annoyingly it’s own, but with Z-Lucky Chant’s x2 evasion… it's more of a monster than ever. Hence why Kommo-o cannot exist because Jirachi!
Anima(Tapu Lele) @ Mago Berry
Ability: Psychic Surge
EVs: 252 Spe / 106 Def / 150 HP
Timid Nature
- Psychic
- Focus Blast
- Moonblast
- Taunt
ANIMA (2) f English (Rare)
Means "soul, spirit" in Latin.
Tapu Lele is very… interesting. It’s got power, it’s got the moves, but it isn’t very fast. So it’s in the middle of powerful and weak. It’s not a glass cannon, but it isn’t made of steel like Fini. But since you already have Greninja, no point in having two water types. :)
Summary
I saw no problems in the choices in your mons, but it's the move sets that gather the wins.
Greninja - kept
Charizard-Mega X - kept
Serperior - kept
Jirachi - kept
Kommo-o - changed for Landorus-Therian
Tapu Lele - kept