All depends on the temperature of the plasma
Fusion plasma can be heated to millions of kelvins. This would be destructive to material projectiles, but would cool extremely fast. It would radiate energy outwards (shining like sun), and inwards (heating the spacecraft skin, and overloading it's thermal management) If your fusion engine is not an absolute torch-drive, and your fuel mass is not high, I don't expect, that such a shield could be sustained for a reasonable time.
Plasma is known for being able to absorb or reflect electromagnetic radiation: https://en.wikipedia.org/wiki/Plasma_stealth
Therefore a plasma shield could defend the craft against electromagnetic radiation. (including lasers) But the usual frequency, below which a plasma is reflective, is normally much lower then that of visible light or x-ray (which could be used in a laser weapon.) To effectively counter laser attacks, much more denser plasmas are needed.
It is very hard to confine plasma with magnetic fields, even when the magnets can surround the plasma (like in a fusion reactor). So, I expect, that a lot of particles will leak, and will be constantly supplied. If the enemy weapon fire gets absorbed in the plasma, it will heat up. If the equilibrium temperature is too high, its particles can acquire so much velocity, that they leave the magnetic confinement, and the shields gets blown away.
A fully deployed high-temperature plasma shield would saturate the passive EM sensors of the vessel, and only let trough active scans, which have higher frequency, than its Characteristic electron plasma frequency. You want this to be high, since you want to reflect lasers, so the shield would render the ship almost blind.
The only really feasible option seems to be a not-too dense, not-too warm plasma cloud. This could be used for radar stealth, but won't mean effective defence against the most attacks. But at least, it could be sustained, without losing plasma or energy.
For game, I suggest, that plasma shield would have a long charging time, while plasma build up in a magnetic bottle, which have extremely reflective supermaterial wall too. The more reduce engine thrust, the faster it accumulates, and the more energy you divert to heating lasers, the warmer it gets. In the critical point, it is discharged in a spectacular flash. Depending on its temperature, it would last for some seconds, fully countering EM attacks, and reducing kinetic damage by 4/5. If enough EM attack s recived, it would last a little longer. It causes some bearable thermal damage to the ship.