Runaways had a rocky start, discovering their parents' evil nature, and, hence, swearing to be nothing like them. However, as it turns out, being a parent might be actually harder than these young Runaways could imagine.
Hidden-Outs is an unofficial (fanfic) spin-off of Runaways (Hulu depiction), which covers a story of several young adults who have traveled back in time to save the world from a bad guy, who happened to not only disrupt their lives, but also is connected to their parents somehow. With the intent to stop the evil, the team tries to catch the baddie only to realize that they have traveled back in time. However, the awkwardness doesn't stop here, as the young team of Hidden-Outs happens to appear in the abandoned hostel, where they meet a group of six young teens, who are known as a Runaways, and their future parents.
Will the Hidden-Outs manage to save the world, win the game of evil, and manage to come back, while trying to do all of this with their "younger parents"? In the original we see Runaways see their parents in one light, but here, it is Runaways' future kids, who happen to witness their parents' younger selves. But let's keep it a secret, no? Who knows how time travel works?