Since it is very difficult to swap armors in this game and at the same time sometimes very necessary, perhaps try this?

Allow us to do something to our gear (like imbue it with Alchemy Stone X + Garmoth Heart) to cause our weapons and armor to have stead of Monster or Human Damage ONLY this effect: Responsive Variable Damage Apply.

What would this do?

Like Armors in real life, you could have the armor change its properties from DR in PvE to Evasion in PvP. 
Likewise, Weapons would be "responsive" as well. You could have it apply Monster Damage to Monsters and Human Damage to humans as it detects which type is present. 

Obviously this seems overpowered, but it solves a number of issues. The overpowered issue can also be easily resolved by creating a further craftings we can do. 

Example:

Grade 0: Garmoth Heart + Alchemy Object + Simple Alchemy converts your ACCOUNT to be able to APPLY "Responsive" Armor or Weapons 

Grade 1: Applies the "Responsive" effect (Requires Alchemy Object) to the Weapon or Armor 
Grade 2: Permits further unlocks (in case you want to create creatures that are necessarily immune this effect except under special conditions). 

Grade 3: Unfunctions furthre off the special conditions clause of Grade 2. 

Etc

It seems for some it's also very difficult to write in the correct forum!