Just finished watching it, so my thoughts haven't had much time to settle, but overall it was pretty bad. I thought I would have a hard time judging the movie on its own and as an MK fan, but it turned out to be rather easy since the movie is bad on its own and is also bad at being anything other than a service-level "adaptation" of the story in the Mortal Kombat games. For the purposes of this post, I will try to judge the movie on its own, then give my overall thoughts as an MK fan at the end.
To me, the story is the most important part followed by the action scenes. As far as the action scenes go, I felt they were sub-par at best with so many quick cuts and bland locations. I felt my eyes glazing over towards the end when they tried to cram like 4 fights into one scene. The old rule of trailers definitely applies to this movie where what you see in the trailer is usually the best the movie has to offer. If you're watching a trailer for a comedy and the trailer is cringy and doesn't make you laugh, then don't expect to laugh in the movie. The action in the trailer for this movie was pretty good, and the action in the film also peaked at about "pretty good."
Sadly, the writing and the story were absolute trash which removed any tension from the pretty-good-at-best fight scenes. From the time they were mentioned in the trailer, I disliked the tattoo thing. I still don't fully understand how they work. I thought they were supposed to appear on champions of Earthrealm, but Kano gets one and that obviously didn't work out. So I guess they appear on people who have potential to be champions, but since they only have a finite amount of space on the roster, the tattoos only go to the top best fighters on Earth, then if one of them dies, the mark appears on the person who is next in line power level-wise? If that's the case, then is the movie saying Johnny is weaker than Sonya, Cole, and Kano, or does he already have a mark and Liu Kang just hasn't recruited him yet for some unspecified reason? Also, does this mean Cole was born with so much potential that he got a mark as an infant? Or is the source of the marks aware of the prophecy (whose origin and purpose are never stated as far as I recall) and has chosen him because it somehow knows that he will be a special top tier good guy fighter?
Speaking of Cole, he was as bland as expected. I also don't know why they cast a half-Chinese guy to play a Japanese character, especially in a movie/world where there are rival clans based in China and Japan, but whatever. I almost gave the movie props for killing his family in order to parallel him with his ancestor, but I suppose Sub-Zero decided he didn't REALLY need to kill the Hasashi bloodline, and chose to just put them on display somewhere for whatever reason. Anyway, I guess Cole's story is that he's just a reckless fighter with poor defensive skills who always gets beat up, so his arcana power is body armor that covers his weakness as well as some bladed tonfa for some odd reason. This kind of suggests that the arcana are somehow related to the user's personality or physicality, but Kano gets laser eye and Sonya gets laser fist, so I dunno, I guess it's random.
Scorpion didn't have much to do other than fight Sub-Zero, but I don't recall them ever saying how exactly he came back other than Cole brought him back somehow. It seems like he was watching him the whole time, but could not do anything until the end where he was somehow summoned. I'm still confused as to how that all worked in the end.
I just realized this is going to be take 30 pages and as many hours if I keep this up, so I'll speedrun the rest of my main thoughts. I hate this Raiden. He seems like an incompetent asshole. He says he can't interfere with invaders from Outworld (which looks awful by the way) even though they are invading Earthrealm and killing his champions in order to cheat in the upcoming tournament. Then he helps them by teleporting them around and when someone says, "Wait, I thought you couldn't interfere?", he smiles as if saying that he actually can. So he CAN help people as Outworld forces run amok killing innocent people and his champions, but he just chooses not to until the very end. Although Sonya may have surprisingly been my favorite character in the movie, she does not seem like Special Forces at all. If anything, she seems like EX Special Forces who got fired or something because she's living in a trailer and never calls for backup, uses any advanced military gear, or even reports to anyone about anything that's going on including letting Kano go free. I got a lot more thoughts in the "weird things that bothered me or didn't make sense" category, but I'll just cut it short here.
So as a fan of MK lore, I knew from the beginning I would have to toss all of my hopes and expectations out the window. The characters are almost completely unrelated to their game counterparts except in the most superficial aspects like appearance or powers. I mean, Kano never gets a cybernetic eye, Bi-Han is somehow 300 years old and ACTUALLY killed Hanzo's family instead of Quan-Chi, Mileena and Reiko are just random jobbers, etc etc. Anyone saying the film respected the source material's story/lore is high as a kite because this thing is its own movie with Mortal Kombat paint.
tl;dr
The movie was bad both on its own and as a Mortal Kombat movie. It's not the worst thing I've ever seen, and the only reason I saw it in the first place (like most probably) was because it was titled Mortal Kombat. Even though I had my gripes with the MK animated movie, that one is far superior to this one. If you're the type who gets an extreme dopamine rush every time you go, "Oh, I understood that reference!" then you'll probably love it.