If Cole Young from the Mortal Kombat movie is added to Mortal Kombat 12, then Netherrealm will have plenty of work to do in order to make him a better character. Cole lacks several traits that more popular Mortal Kombat alumni have in spades, and that works to his detriment. Although he is not completely inviable as a character, he needs much more development.
Cole was considered to be the movie's weakest aspect by several fans. Being an original character playing the protagonist in a film based on a popular game franchise, he had to deal with a negative stigma from the start. While not outright horrible, he still lacked anything truly special and ultimately proves too weak that some argue Cole should be killed off in the sequel. A game appearance could fill those holes in his character and make him a genuinely solid addition to the roster.
There are a few areas that Cole needs to work on in order to be a good Mortal Kombat character, and all of them can be believably achieved. He may be starting in an unenviable position, but Netherrealm has made great characters before, and they can do so again. With proper buildup, Cole Young can be another engaging member of Mortal Kombat's roster.
Every character in Mortal Kombat has their own recognizable fighting style. For instance, Jax has his mechanically-enhanced boxing, Mileena has lightning-fast kicks and sai strikes, and Sheeva is a powerhouse brawler. Cole, on the other hand, is a fairly average fistfighter without anything special about his technique.
Where Cole does have a chance to stand out is his power. Cole has the power to manifest armor, as well as a pair of tonfas. Making heavy use of these would be key to giving him an interesting moveset in Mortal Kombat 12. Cole could replace his pedestrian fisticuffs with a variety of tonfa techniques, although with him still being new to the weapons, his swings would likely use more brute force than finesse. In addition, with his armor's ability to absorb blows and redirect their energy, he could make use of a few counter abilities, giving him a gimmick of being a more defensive fighter.
Lacking his own identity as a fighter plagued Cole for most of Mortal Kombat's runtime, so focusing on his more unique talents will help him stand out in a good way. His tonfas and weaponized armor are a combo that no other character in the series has, so they will help him find his identity. With the Mortal Kombat tournament still happening after the film, Cole will need his own signature fighting style to stand a chance.
One of the major things that held Cole back in the Mortal Kombat movie is the fact that he seemed like the most incompetent character in the cast by a wide margin. The series is full of powerful and dangerous fighters who can conceivably pose a threat to each other. Even resident funnyman Johnny Cage is a serious competitor in a fight. However, Cole is easily a few steps below the rest of the cast in battle, so he desperately needs an injection of competence in Mortal Kombat 12 to be taken seriously.
It needs to be stated that in the movie, Cole is a mediocre fighter. Cole's first scene may have foreshadowed his powers, but it didn't show him to be anything special. Even as an MMA fighter before joining the Earthrealm champions, he was a poor fighter with little skill. One he starts fighting members of Mortal Kombat, he continues to perform poorly, even after gaining his armor and tonfas. He does not impress in his fights, at least on his own, frequently needing help to win. If he is in Mortal Kombat 12, then Cole needs some time to show that he has improved his skills, and can fight on even ground with the others.
Cole has a serious lack of credibility as a fighter, and that would absolutely need to be addressed in Mortal Kombat 12. He needs to be portrayed as someone who can actually win a fight on his own, otherwise he simply cannot be taken seriously. If Cole can't be improved in this regard, then maybe Mortal Kombat 12 doesn't need Cole Young.
Admittedly, Cole already has a connection to the Mortal Kombat mythos, being a descendant of Scorpion. However, he has the issue that he doesn't really feel like a Mortal Kombat character. Although that may be the point, with him basically being an outsider that was drawn into the tournament, it creates a bit of a barrier between him and the rest of the cast. He doesn't feel like he belongs, and Mortal Kombat 12 could seek to change that.
Cole is largely reactive as a character. He is a character who, much like the audience, is just being introduced to the world of Mortal Kombat and trying to comprehend it. However, this is a role that could have easily been filled by Johnny Cage, who is absent from the film. Unfortunately, outside of his love for his wife and daughter, Cole doesn't have an especially established personality. Cole may be Scorpion's descendant, but he lacks his ancestor's charisma and coolness factor. If brought into Mortal Kombat 12, Cole absolutely needs a stronger personality, or else he will be completely ignored.
One good way to flesh out Cole's personality would be through further interaction with other characters. He needs to show more agency and become a distinct character of his own, rather than a bland figure in a cast of vibrant and interesting characters. Netherrealm could make him more inquisitive, or even constantly surprised by the absurdity he is now a part of. He needs something to make him interesting, and a change of personality could do the trick. Cole Young a Mortal Kombat protagonist, and he has to live up to the title.
As Mortal Kombat's newest character, Cole has a lot to live up to. The games already have a rich selection of characters, and as a not-especially-popular newcomer, it will take a lot for him to live up to their legacy. However, with Mortal Kombat 12 being as hyped as it is, if NetherRealm does decide to include Cole, it would be wise to work on the aforementioned traits.