Now that I've tried Overwatch and Paladins, I'll probably compare them both.
Overwatch is a really good game, but it has a lot of flaws and frustrations (this is based completely on my own opinion of course), that are going to frustrate the hell out of you.
For one thing, the amount of abilities/attacks in the game that can instagib you is...unbelievable. And often times you'll have no idea how it happened (until you see the Kill Cam of course). But what I mean is, you can get killed instantly while having no idea what hit you or where your opponent was. Often, the abilities that do this are hero "ultimates", so in that way it's somewhat forgivable but not really because the ultimate charges really fast and I've seen people used their ultimate multiple times within the same minute. The best you'll get is an audible indication (the enemies usually say a specific audible line before they use the ult), but the thing is, there's 21 characters, and they all talk constantly, so learning the specific voice lines of the ultimates of every given character is...going to take awhile.
Then of course there's a lot of non-ultimate abilities that can either kill you instantly or near-instantly. Black Widow sniper rifle headshot can kill most characters instantly, but even a full charged body shot will usually take 7/8ths of your health, so if you were hurt in any way before or after that, you're dead. Bastion can morph into a huge Gatling Gun that is deadly accurate even at extreme ranges and will kill most characters in a second or two. Hanzo is the same as Widowmaker. If you accidentally walk into a room full of Symmetra traps you're more or less dead instantly. If you accidentally step into Roadhog's bear trap you're ensared for eternity, so in a fast-paced FPS that basically means you're dead.
Now of course, all the ways the game has provided to kill you instantly would be okay, I suppose, if you could actually get back into battle, but you usually have to wait about 10 seconds after you die; and I haven't even told you about the worst part of the game yet. The worst part of the game is DEFINITELY the travel times. The distance between your spawn point and any given objective destination is sometimes 30 seconds or more. It's very easy to get lost on the way because the maps usually have tons of rooms and paths that are dead ends, and it's never very clear how to reach your goal in the most efficient way possible.
Often times, you will have spent more time walking than actually playing the game. Since there's no 'sprint' feature, and since the objectives are so far away from the spawn point, expect to spend a lot of time doing this. However, neither of these two mechanics (the sheer level of instagib and walking distances) on their own are too unforgivable, it's only when you combine them that it often makes the experience of playing the game unbearable.
A situation occurs very often where you'll walk across the entire map after you've died to get to your objective destination, and then die instantly to some stupid ability or character who knows the map better than you, and was hiding in a corner or on a rooftop you didn't expect. Now you get to watch a glorious ten second cutscene of them gleefully killing you, then walk across the entire map again. This can happen over and over and over until the entire match was basically spent dying, waiting, respawning, walking, then dying again. I expect this to make Misery extremely ragey, and I look forward to the inevitable post.
Now of course, there are ways to limit this. One obviously is to be a good player. If you don't die often, you get to enjoy the game. Knowing the maps really well helps because then you're less likely to get killed from an angle or location that you didn't even know existed. Also knowing the maps means knowing the fastest route to your destination (less time walking). Playing tank characters means you're liable to last longer in battle, though you can still die pretty damn quickly, and often one of the frustrating things about the tank characters is that they're just giant, hulking targets that everybody focuses. They also move reallllly slow compared to the lighter characters, so if you don't have a healer, it's tough to find a health pack. Also few people like to play healers. Expect to die a lot.
One other fatal flaw of the game is that it cycles through the maps on its own, without even giving you so much as a vote on which one you'd like to play next. IF you could practice the same map over and over (this is what I do in CS:GO, I learn each map one at a time competitively because it's a lot more fun when I don't die because I have no idea how the map works), then it would probably be a lot more enjoyable because at least then you would know where the most common camping spots are, and how to get to your destination the quickest way. Knowing a map well in games like these is extremely important for more reasons than I care to list. However, since it seems you really have no say in this, you're basically going to get thrown on any of I'd say a dozen maps or more, so expect to get killed in confusing and frustrating ways for the first 100 hours or more until you have a decent handle on all of them.
In that way, Overwatch very much resembles a typical MOBA. Not just because of the cartoony art design, the individual hero mechanics, the ultimates, the audible interactions, the objective-based design and everything else like that, but also because for most people it has such a massive time tax. And you can be sure that unless you're a 15 year old kid living in his mother's basement, most players are going to have spent a lot more time on the game than you have, giving them an incalculable advantage. Let me put it to you this way, there is no company in the world who has players sinking more hours into their games than Blizzard. World of Warcraft? I rest my case.
It also resembles a MOBA in your reliance on the team. It's not a typical team shooter (Battlefield or CSGO) where an individual player can clinch the game on his own. Since the heroes are separated into classes, each class is usually necessary to achieve victory, and so you can only perform your role in the game. Your role is of course, limited, and therefore your reliance on the other 5 players is heavy. If your team sucks, expect to lose.
Now of course, one could assume that given all the negative things I've had to say about this title that it's a bad game. It's absolutely not. As I said, there are solutions to most of the problems, but they usually require a time and commitment that most people on this forum are going to have no interest in, even if with their busy lives they could give it.
In some ways Paladins is nice because being instagibbed from full health is rare, you usually see the enemy players before they kill you, the maps aren't that complicated, and the hero mounts make travel so much faster which means you don't have to spend 30 minutes walking between your spawn and the objective. Overwatch obviously has the advantage in production value however, and you're going to feel that instantly.
Which isn't to say, once again, that Overwatch is a bad game, but do not let the cartoony style fool you. It is extremely and unforgivingly hardcore.