you would more dual wield a deflecting type and a striking type. a tonfa does make a good deflecting weapon, but a shield would be more ideal.
the best though would be another tonfa, almost all kobudo systems were set around dual tonfa, there is a reason for this, and that it wasnt used with a sword or spear, which the okinawans did have both. their sword and spears would used with a sheild
If you're going sword/tonfa, you might as well go sword/shield, cause that is what you'd be using the tonfa for, and a shield would definitely shield you more than a tonfa. A tonfa is really good for deflecting a weapon and then striking very quickly, much like Escrima sticks, but pairing it with a sword, is like, well if the weapons had personalities the tonfa would feel like he can't get out of the sword's shadow.
Why go so complicated? If you had even one tunfa and knew how to use it and incapacitated your opponent there is no need for another weapon. Incapacitated is incapacitated no matter how many weapons you have. The more complicated you make something the more opportunities for error and an error in a fight will lose you the fight.
Your idea may look good for fantasy and in fantasy you can pair anything you want and even have tunfa with blades attached to them but it is hardly realistic.
you can use dual swords, dual nun chucks, dual knives, almost any weapon can be used dually.
I know dual tonfas would probably be the best but I'm curious if you could efficiently use a sword/tonfa style.
