Dark Deed's page

The (other) enemy has Retributive strike but no champion's aura, and retributive strike refers to the aura to determine the range.

I'd ignore the prerequisite of having used twin parry. The enemies were given these reactions for a reason, and to me it seems clear that they are supposed to be able to use the reactions too, so I'd just let them twin riposte as a reaction if someone critically misses them.

https://2e.aonprd.com/MonsterAbilities.aspx?ID=31

What you suggest might lead to this:
Player 1-3 play repetables up to lvl 4. Then give all their gold to lvl 1 player they have been cooperating with. Resulting player having like 300 gold above their paying grade. Repeat 3 times, and we have player with over 1000 gp at lvl 1. This completely breaks balance.

I still have local VO refusing to give access to all characters, saying "You" means character.

I wish we'll have clear boon text. Not so hard to replace "You" with "Player".

So, page with boon says:

Avid Collector - Guns Weapons Select an uncommon item from a curated list of Pathfinder Guns & Gears options; all of your characters have access to it. Can be purchased multiple times on the same character; select a different item for each purchase.

But boon text is as follow:

Avid Collector - Guns Weapons
Avid Collector—Guns Weapons: As a Pathfinder, you periodically come across obscure items that are unfamiliar to most other adventurers. Select one of the uncommon items from the Pathfinder Guns & Gears listed below when you assign this boon to a character. You have access to the item, allowing you to purchase it.
You can assign multiple copies of this boon to a character, each time selecting a different item.

Local online GM says boon text trumps general text, so part where all characters gets it is a mistake.

Can we have an offical answer to that?

So, there is an item called Iron lord’s transforming slivers in Inner Sea Gods. It text says:

The metal flings within this pouch are a mixture of adamantine, cold iron, mithral, and steel. The flings are faintly magnetic and stick to ferrous metal but are easily wiped away. If a metal or partly metal weapon is covered in the entire contents of the pouch and placed in a hot forge overnight, it slowly grows or shrinks by one size category toward the size of the creature who applied the powder. For example, a Small +1 longsword coated with the flings by a Medium creature transforms into a Medium +1 longsword. This transformation is permanent. The pouch contains enough material to transform one weapon, regardless of size.

The question is, does that item effect presist between adventures?

Things that speak not in favor of that is in game guide:

A character can have one each of the following spells
on an item or items that carries over from adventure
to adventure: continual flame, masterwork transformation
(Pathfnder RPG Ultimate Magic 228), secret chest, and
secret page.

Things that speak in favor of that is in FAQ:
http://paizo.com/paizo/faq/v5748nruor1hh#v5748eaic9vhw

If a magic item creates something like an additional item or currency, can I keep it?
Yes.

But our Regional VC ruled that this item effect does not presist between scenarios.

Keep in mind that this item can not be abused to create more costly item by the Guide:
Equipment: If the price of an item becomes more expensive, you must sell back the affected equipment at its original full market value based on its remaining number of charges (if any). So long as you have enough gp and Fame, you can purchase the same item at its updated cost.

So here is the real question.

I currently got one character with Butchering Axe that I got from a chronicle sheet. I asked a large creature for me to use that item and played serval scenarios. To wield it, I have taken a level in Titan Fighter. Since axe no longer can be large, can I retrain that level of a fighter for free? Or I have to pay full PP/GP cost for it? Can I also get my gp for item back?

Same question about my summoner, where I used said item to make adamantine Bastard sword Huge (paying the diffrence cost). Can Eidolon retrain EWP feat for free? Can I chose another weapon and get the diffrence in gp (I would rather swing greatsword then, rather than bastard sword)?