Can Star Wars: The Black Series Force FX lightsabers like this one be used for dueling? Unfortunately, no, because Star Wars Black Series Force FX lightsabers use string blades. String blades are lightsaber blades where the LEDs are contained within the blade itself. During heavy dueling it would easy to disrupt or damage the LEDs within the blade. Damaging the in-blade LEDs creates unattractive dead spots in the blade.
The plastic for the blade is relatively thick, so you would be able to do some very mild dueling, but you definitely don’t want to do any heavy dueling due to the high risk of damaging the LEDs inside of the blade.
Some people do choose to convert Star Wars Black Series Force FX lightsabers into duel worth sabers. Force FX conversion is a process that entails removing the string blade from the hilt and replacing the string blade with an in-hilt LED and detachable polycarbonate blade. The Force FX conversion process is NOT very easy and converting different model hilts involves different steps. There are several Force FX conversion tutorials around the internet. Alternatively, some people choose to hire someone to convert the saber for them.
In summary, a Star Wars The Black Series Force FX lightsaber is NOT DUEL WORTHY right out of the box, but you could convert the saber into a duel worthy saber or hire someone to convert the saber for you.