You could mess with the mass of the projectile or change the gravity force of the object to mess with some interesting shots. Or do you not want it to curve at all?
Good to know it is melee, but i am still having a hard time figuring out why it would curve at all since its melee. Can you post a screen shot of the attack? Is it a sword swing, punch, etc.? I cant imagine a melee attack curving since normally it is an animation of some sort.
I fixed this problem, well my attack curved in the air because the gravity force (-34) was too intense I “fixed” this adding a Vector2.up now looks great. Thank you for your time.