Here are the Weapon suffix/prefixes I have encountered while playing.
Weapon prefixes/suffixes
Enchanted - +20% Spell Damage(wands only)
Guardian's - +20% Block Rate(swords only)
Scoped - +20% Critical Rate(guns only)
of Regeneration - Regen in Combat(Approximately 5% of max hp)
of Life - Constitution +1
of Power - Strength +1
of Speed - Quickness +1
also, i'm not sure if those(enchanted/guardian's) are weapon specific