I can see 4 different variations that NRS team could use but only 3 are allowed, I list them below.

1 Varation: Psychopath - Based on his Appearances from Part 2,3,4,Remake so Human Jason. He can be a rush down melee character since as a human he could run, he could use things like a bow & arrow for projectiles and a harpoon gun and such, Also since he didn't use the machete that much in those films maybe he can use an Axe instead since in Part 3 he used this for most of the final act.

2 Variation: Undead - Based on his Appearances from Part 6,7,8,10 & FvJ so Zombie Jason. Since he is a Zombie he won't run but would make up for this by having his basic attacks do massive damage to the opponent and also have some grab>stab>slam like grapple moves and since he is a zombie can have a mode he can enter where he can regenerate a bit of health while fighting since in this form it was stated that he can regenerate tissue, And instead of shooting arrows & harpoon guns he can throw daggers that he has on him like he has done in part 6 & 7

3 Variation: Hellbound - Based on his Appearance from Part 9 (I know Jason Goes To Hell Sucks! But what the hell) Since this is Demon Jason he can be similar to Zombie Jason with his high power damage but have it toned down a bit and also his walk speed can be faster than Undead but slower than Psychopath so somewhere in the middle. It's also possible that he can have a summon attack where he sticks the magic dagger used to send him to hell in the film and summon those giant hands to attack the opponent for a range move, He can also have a life absorbing move as a grab since in that film he can posses your body if he can get his demonic worm form inside you, Speaking of which that worm demon can be used as a floor projectile too like a Power Wave Move(Terry Bogard), And finally the orange glowing orbs that exit his body at the end of the film which also are the ones used to posses the coroner in the beginning of the film can be used as fireball projectiles too idk. So all in all a Sorcerer based Jason as wired as that sounds lol

4 Variation: Upgrade - Based on his Mecha Armored Appearance from Jason X. Since this Jason is covered in Armor he can have a Super Armor property to his character, Think of Hulk in the 2d MVC games where you had to hit him 2 or 3 times to break the animation he was doing, or heck think of Doomsday's Button trait in Injustice. This Jason could have more Knockdown like moves that should knock you down and off your feet with one hit, Whether it be a shoulder tackle or a straight charge punch. Since in this form he has android like parts in him he won't be slow like Undead or Hellbound Jason would be, So this can be the 2nd fastest Jason of the 4 I have. That's all I have for this Jason, Basically Armor Brick base like defense with Heavy Attack and some speed to him.

So out of the F13 series I though of these 4 variations they could do but the problem is, They can only include 3!? Question is which 3 would you want!?