Re: Pathfinder Erza
First, you have to legally own each weapon that you want to summon. If you have the Craft Magic Arms and Armor feat, you can make your own weapons. This means you have to pay the real cost for every weapon. That's how it would be done fairly. You couldn't summon a weapon that belongs to others without their express consent. Otherwise, this is theft.
Second, You'd also probably need a bag of holding to carry those weapons in.
Third, if you want this nifty ability you'd have to give up something for it. Pathfinder allows for all kinds of swapping of abilities (see Archetypes).
Fourth, how fast you can swap one weapon for another might scale over time. Considering that Erza is pretty powerful, this is not something that you'd have access to at low levels.
For example, Requip could allow you swap any weapon you are currently wielding for any other that you are carrying (must be on your person or in your bag of holding) even while you are in combat as a Standard Action.
P.E.A.C.H. Please Evaluate And Critique Honestly. Being nicer and kinder doesn't hurt either.
Please, please, please when using non-core material, cite to the books. There are too many books to wade through to find the one with the feat, special ability or spell you use.
I've got a red
pen and I'm not afraid to use it.