No problem, either concept is fine.
WD:
To my best knowledge, Miyamoto Musashi used two-weapon fighting and katanas successfully.
Hook swords, chicken sickles, tonfas and other Asian weapons were/are also often used in pairs.
Musashi is a historical figure but with much myth surrounding him. One tale, for example, shows how he carved a nodachi out of an oar as he was heading over for a life-or-death duel on an island. He beat his opponent with it.
Needless to say a hastily carved wooden sword can't match a real weapon unless you are fighting someone with 0 skill (which was not the case as far as the story goes).
Using two equal length weapons longer then daggers in each hand is pretty much fiction yes. I believe one of the medieval masters of the sword said that in order for one to use two swords in each hand effectively, he must be as good with his off-hand as he is with his primary hand (in other words, he must be perfectly ambidextrous).
There are also modern day researchers of swordfigthing and WMAs, (ARMA for example, google them). They say that during practice sessions they have found no real advantage to wielding two equal length swords (such as longswords). They would rather be fighting with sword & buckler, sword & shield, or just with two hands (and the off-hand available for grappling).
Same with daggers - they'd rather be able to grab your ear or grapple your hand then have a second pointy thing to stab you with.
Short weapons, like the katar for example, were in fact, dual wielded. But that is a whole different style from swordfighting (it's as close to swordfighting as wielding a spear is). Just because you have bladed weapons and stab/slash with them does not mean you qualify as a swordsman.
There are great misconceptions added today by Holliwood. Like the guy grabbing a greatsword and cleaving trough plate with it. Historically, greatswords were used much like spears (that's why the bottom part of the blade is wrapped in leather) and were used primarily as thrusting weapons when fighting an armoured foe.
During ancient times a shield was actually a preferred sidearm, and while not "cool" enough for the movies, it's very very useful in battle. Think about it. In the thick of a melee, would you rather have another sword (although a single strike from a single sword is enough to end a fight. Even a graze trough the muscle on your hip for example) or a thick shield to keep the enemy pointy things from reaching you in turn?