Spends 5 minutes setting up for an attack the Gunlance, GS and LS match in damage

HAMMER

I want a weapon that is just a huge-ass pizza cutter axe
Make it reasonably slow but extremely hard hitting, with some sort of rev up mechanic that makes the axe spin faster and hit harder, launching you forward and to the sides from the sheer impact.

As a GS main even I can admit CB feels really fucking good to use even if the damage is piddly peas.

dual blades require too much unga clearance to really be good for new players. new players will 100% need at least 3 points in evade and divine blessing 3 to not get fucked before they figure out the weapon

hammer or hunting horn.

The damage output is one of the better ones for melee, the only problem with World's CB is that Iceborne fucked the GPs and that AED/SAED are too slow now to be spammed, which is a good thing on the other hand since it makes the weapon less braindead.
Other than fixing those I'd make it so CES is chargeless and lasts more, sword buffs are too good to give up and having to wait one second or so until being able to release CES is just pointless and adds nothing to the weapon other than the cool factor.
No reason why you can't just add that to the moveset without sacrificing anything, make it some kind of pilebunker Clutch Claw attack like ZSD, or make it so the shield jab can be charged into it if you have full shield buffs.

the real thing gating chargeblade is the sheer amount of pre-req abilities that you need to get