Over and Over is a yalex soulmate timeloop au fic! (Title taken from the three days grace song of the same name)
The basic premise (which I have seen only once and have been OBSESSED with ever since) is that the first time you see your soulmate, it starts a timeloop that only the two of you experience. The first day of the loop is the only "real" one and the rest is just the two of you like, getting to know each other.
Once you figure out who you're in the loop with (which can be somewhat difficult because like, you could literally have just seen them across a busy street), you basically get three years to fall in love. If you don't fall in love within that timeframe, you forget who your soulmate is and everything that happened in the loop, but do remember that it happened so you're not like, waiting your entire life for something that already occured. And if you die in the loop, you die in real life.
So, cue Alex and Yassen waking up after that meeting in Point Blanc only to realize that they're looping, resulting in VASTLY different reactions. Yassen is like "he's sixteen and made of hormones and being manipulated by MI6, just doen't lie to him and sleep with him until he falls in love with you, and then take him back to scopria's loving arms" and proceeds to set out to do just that.
Alex, meanwhile, is completely cut off from his support system and, you know, a fucked up grieving mess essentially trapped behind enemy lines. So he decides to be even more reckless than usual and like, gets himself into all kinds of trouble. And then, you know, when he finds out that yassen killed Ian has a complete breakdown about what that means
Eventually Yassen realizes he actually doesn't want Alex anywhere near any of this, and so he and Alex have to actively fight catching feelings with each other so that they have enough time to get dirt on scorpia and MI6 so they can both get out and retire once the loop is over.
This was my nano this year and has 50k+ and is still nowhere near done, given how complicated it is. But one day! I will finish!