New team line up

So I'm trying to make a team with favorites but the last few times I've tried, I ended up missing a few things, lemme know if this is ACTUALLY usable. (without Smogon tiers)

Excadrill
Jolly
-Earthquake
-Rapid Spin
-Iron Head
Shadow Claw/Spikes (if possible)
Ability: Mold Breaker
Item: Air Balloon (only if it avoids Spikes set by the enemy)
EV: 252 Atk/252 Spe/6 HP

Shuckle
Relaxed
-Infestation
-Shell Smash
-Toxic
-Rest
Ability: Contrary
Item: Chesto/Sitrus Berry
EV: 252 HP/252 Def/6 SpD

Infernape
Naive
-Stone Edge
-Flare Blitz
-Thunder Punch
-Blaze Kick/Close Combat/U-Turn
Ability: Iron Fist/Blaze
Item: Life Orb
EV: 252 Spe/252 Atk/6 HP

Rotom-W
Modest
-Hydro Pump
-Volt Switch
-HP Ice
-Thunderbolt
Item: Choice Specs/Scarf
EV: 252 SpA/252 Spe/6 HP

Lilligant
Modest
-Petal Dance
-Energy Ball
-Aromatherapy
-Giga Drain
Ability: Own Tempo
Item: Focus Sash/Band
EV: 252 SpA/252 Spe/6 HP

Gengar
Timid
-Sludge Wave
-Shadow Ball
-Dazzling Gleam
-Perish Song
Item: Gengarite
EV: 252 SpA/252 Spe/6 HP

Would this team do good?

Also if need be, I can replace 1-2 with Aegislash and/or Porygon-Z

Porygon-Z
Modest
-Thunderbolt
-Ice Beam
-Tri Attack
-Dark Pulse/Shadow Ball
Item: Choice Specs/Life Irb
Ability: Analytic
EV: 252 SpA/252 Spe/6 HP

Aegislash
Quiet
-Shadow Ball
-Flash Cannon
-Toxic/Sacred Sword
-King Shield
Item: Weakness Policy
EV: 252 HP/252 SpA/6 Atk

As your team currently stands, half of it is weak to Water. Things like Manaphy, Starmie, and Feraligatr can easily tear through it once the resists are taken out.

The only entry hazard Excadrill learns is Stealth Rock, which is more useful than Spikes, as it hits all types, even those with the Levitate ability. IMO, Excadrill should be bulky if it were to set up Stealth Rock, to take advantage of its good defensive typing. Air Balloon is best left to the Sand Rush variant of Excadrill (which must be paired with Tyranitar or Hippowdon to be effective):
-Earthquake
-Iron Head
-Rapid Spin
-Toxic/Stealth Rock
Nature: Careful
EVs: 252 HP/4 Atk/252 SDef
Item: Leftovers
Ability: Mold Breaker

A less popular, but still viable, variation of Excadrill is Choice Scarf to let it act as a revenge killer and still be able to clear away entry hazards in a pinch:
-Earthquake
-Iron Head
-Rock Slide
-Rapid Spin
Nature: Jolly
EVs: 252 Atk/4 Def/252 Spe
Item: Choice Scarf
Ability: Mold Breaker

Shell Smash + Contrary Shuckle may seem tempting to make it even harder to break, but it's very passive and makes it setup bait for other sweepers. Its only niche is a Sticky Web setter to slow down grounded opponents:
-Sticky Web
-Stealth Rock
-Encore
-Infestation/Toxic/Knock Off
Nature: Bold/Impish
EVs: 248 HP/252 Def/8 SDef
Item: Mental Herb
Ability: Sturdy

Close Combat is a mandatory move on Infernape, as it's a hard-hitting Fighting STAB:
-Fire Blast/Flare Blitz
-Close Combat
-Gunk Shot
-Mach Punch/Grass Knot/Hidden Power (Ice)/Thunder Punch
Nature: Naive
EVs: 100 Atk/156 SAtk/252 Spe or 188 Atk/68 SAtk/252 Spe
Item: Life Orb

Wash Rotom is better off defensive, as going on the offensive will make it face competition from its fellow Electric and Water Pokemon:
-Volt Switch
-Hydro Pump
-Will-o-Wisp
-Pain Split/Rest
Nature: Bold
EVs: 248 HP/252 Def/8 Spe
Item: Leftovers/Chesto Berry

Simply put, Lilligant is outclassed by Serperior as an offensive Grass Pokemon because the latter can boost its Special Attack faster with Contrary Leaf Storm, and packs neat utility options (mainly Taunt and Glare). I wouldn't even consider Lilligant in the first place if I were you, due to its pitiful movepool.

Perish Song Mega Gengar is better off in a stalling role. First it uses Perish Song, then any combination of the other below moves to stall out the opponent. Mega Gengar must switch out the turn before its perish count hits 0:
-Perish Song
-Protect
-Taunt/Disable
-Substitute/Disable
Nature: Timid
EVs: 248 HP/84 SDef/176 Spe
Item: Gengarite

Offensive Mega Gengar is better off without Perish Song; it should use its offensive moves to take out weakened targets or, if Mega Gengar is weakened, try to take the opponent with it using Destiny Bond:
-Shadow Ball/Focus Blast
-Sludge Wave
-Taunt/Protect
-Destiny Bond
Nature: Timid
EVs: 4 Def/252 SAtk/252 Spe
Item: Gengarite

As for your alternate options, Porygon-Z is better off with either of its regular abilities, Adaptability or Download. It's unlikely to ever take a hit or force switches to make the most out of Analytic. Better sets are Choice items + Trick or a double dancing set (picking a boosting move based on the team you're up against):
-Nasty Plot
-Agility
-Tri Attack
-Dark Pulse/Shadow Ball/Thunderbolt
Nature: Modeset
EVs: 80 HP/252 SAtk/176 Spe
Item: Life Orb/Lum Berry
Ability: Adaptability

or
-Tri Attack
-Dark Pulse
-Thunderbolt/Ice Beam
-Trick
Nature: Timid/Modest
EVs: 4 Def/252 SAtk/252 Spe
Item: Choice Scarf/Choice Specs
Ability: Adaptability

Toxic on Aegislash is better off on its own dedicated set (SubToxic). Aegislash benefits more from 3 attacking moves + King's Shield:
-Shadow Ball
-Iron Head/Flash Cannon/Shadow Sneak
-Sacred Sword/Shadow Sneak
-King's Shield
Nature: Quiet
EVs: 252 HP/252 SAtk/4 SDef
Item: Leftovers/Weakness Policy

or
-Substitute
-Toxic
-King's Shield
-Shadow Ball/Flash Cannon
Nature: Modest/Timid
EVs: 252 HP/252 SAtk/4 SDef (Modest) or 252 HP/4 SDef/252 Spe (Timid)
Item: Leftovers

And I'd like to make a point about tiers here. The point of tiers is so you can use your favorite Pokemon without it being overshadowed by the generally better ones in the standard (OU) environment. If your favorite Pokemon is in the UU, RU, or NU environments, feel free to play in those tiers and make teams around that Pokemon. Of course, you don't have to, but I still want to make that point for you to consider.

I'd rather not use Serperior, as I don't like that Pokémon.