The alch version gets to play with different class levels and ap that the EK version does not due to having a feat for int to damage on simple weapons. That means moar dice and dps. Against neutral targets ( targets that are not vulnerable or immune to your specific element ), the alch version puts out more damage. EK has the advantage in quests where changing targets doesn't require stripping immunity on a cooldown.
Class ap :

Feats :

ED: Shiradi 33/SD23/Draconic ~14. If you have a raid party where others cover SD debuff then put 20+ into draconic instead for the one minute wellspring.
Gear is pretty much the same as EK build except it swaps in dread Sky necklace and ring and swaps out Sea versions. Trinket and Ring from Legendary Silver Concord set.
Googles: Legendary Lenses of the Dark Depths (Ins Dodge, UMD, Blindness Immunity) Profane Experiment 1
Helm: Watcher helm (Ins DS, Accuracy, Q Deadly, Seeker) Perfect Silence 1
Neck: Legendary Pendant of the Sky (Insight Negative/Devotion, Deception) Curse 1
Trinket: Legendary Gem of Many Facets (Insightful PRR ) Silver Concord set Concord 1
Cloak: Cloak of the Hunter (Relentless Fury, Exc Healing Amp, Q Deception, Q Seeker 3) Perfect Silence 2
Belt: Dinosaur Bone Belt (Int 15, Deadly, Armor Piercing) Curse 2
Gloves: Legendary Birchlore Curse 3
Boots: Legendary Spectre Boots (Doubleshot, Ghostly) Profane Experiment 2
Bracers: Legendary Sunken Chains (Insight Seeker, Q Int +3) Perfect Silence 3
Ring: Legendary Signet Ring of the Sky (Negative 149, Positive 149) Curse 4
Ring: Legendary Ring of the Silver Concord Concord 2
Armor: Legendary Researcher's Leathers (Healing Amp, Fort, PRR, False Life) Profane Experiment 3
Weapon: Attuned Bone Heavy Crossbow (Icescale, Meltfang, +2 Exc Int, Ash) Curse 5
Quiver: Epic Quiver of Alacrity (Insight Deception)
Filigree :
artifact spines raid 10rp/beast mantle 5 rp/snake bite attack-damage/long shadow 5rp
weapon
spines raid 10rp
set : 2 dmg
total : 20 rp/2dmg
long atk/dmg
long 5rp
set : 5rp/2 dice
total : 15rp/1 dmg/2 dice
beast mantle 5rp
beast mantle +1 con
beast mantle +1 str
set : 10 natural armor/10 fort bypass/2 imbue dice
total : 2 imbue dice/10rp
reverberation 10 universal sp
reverberation 4 usp
set : 2 dice
total : 14usp/9 sonic power/2 dice
snake bite attack and damage
snake bite/grandfather +2con
set : 2 dice
total : 2 dice
total dice :
5 alch 15 levels
4 aa ap
2 drow ap
3 assassin ap
7 inquisitive ap
2 chaos feat
3 scion feat
1 elemental dice feat
6 filigree
1 augment
3 gear set bonus
2 greater elemental weapons
3 draconic
42 dice