I am currently playing Paladins, which is a F2P hero-based shooter very much "inspired" by Overwatch. Granted, if I had bought Overwatch after the open beta I probably would not be playing this at the moment. However, I have some sudden free time and I felt like playing a shooter, and I have been very pleasantly surprised. I expected a poor man's Overwatch, but the gameplay is very smooth and responsive, and some of the differences from Overwatch actually make it a much more enjoyable experience to me. There is no pay to win, only pay to unlock the heroes faster and pay for cosmetic stuff, but so far the in-game currency accrues faster than I can learn new heroes.
Every player spawns with a mount for transportation, so there is less walking time. Killing also takes a bit longer than in Overwatch, so overall there is a lot of combat time. There are roles like tank and support, but they are less specialized so there are no classes that do junk-tier damage. In Overwatch the support classes largely felt like a chore to me, but in Paladins I find all roles very interesting. Also, boring Mercy full team revives. There is no mid-game hero switching, instead there are card load-outs for each champion and within a game there are buyable items. With these you can adjust your playstyle or build reasonably well to account for the composition of the enemy team. These offer quite a lot of depth.
Now I haven't played enough or even with a full stack on voice chat to decisively judge the balance or the game design, but the game seems reasonably competitive, and I am having fun. It's worth a shot if you are too cheap for Overwatch, or are frustrated by it.