Because of the rules regarding category sizes it is not very handy to use something like a medium-sized longsword as a creature of size category Large or Huge (because of the -2 or -4 modifyer on hitting someone). The Arms and Equipment Guide has a possible solution: the Fullblade. A Huge-sized exotic weapon that a Medium creature needs a feat to be able to wield, it should be a perfect fit for a Huge creature... I think. It makes mention in the text that a Large-sized creature can use it with two hands like a regular two-handed weapon, but I am not sure if this invokes negative modifyers. So I wonder the following:
How does wielding a Huge weapon designed for a Medium creature affect a Huge creature? How about a smaller creature? Or is a better alternative than the Fullblade?