In Short: Hangouts Chat has just received a rather useful feature, you can now snooze notifications with the app / service. Hangouts Chat now allows you to choose a time frame in which you'd like to keep notifications silent, you can snooze notifications for 30 minutes, or one, two, four or eight hours. If you do this, your notifications will be silent across platforms. So, for example, if you do it on your desktop PC, the same will apply for your smartphone, same as it works with regular Hangouts application. Other users will notice you've snoozed your notifications, however, when you're in the 'snooze' mode, other users will see your present indicator change, it will become a moon, and the status line next to it will let people know when you'll be disposable again, in other words, when will your notifications unsnooze.
Background: Don't mistake Hangouts Chat with Google's regular Hangouts app, as the two are quite different. Hangouts Chat is a G Suite service, it's a messaging platform created for teams. This app is supposed to help teams get their work done in one place, as it offers virtual rooms for cooperation. Threaded conversations are supposed to help teams complete tasks, and Hangouts Chat supports 28 languages, while each of its "rooms" can support up to 8,000 members, just in case your business is on the larger side. Hangouts Chat offers deep integration with Google's G Suite portfolio, including Drive, Docs, Sheets, Hangouts Meet, and so on.
Impact: Hangouts Chat has been around for a while now, but it still lacks some of the features that are available in the regular Hangouts app. That is not all that surprising, though, as Hangouts Chat does not have the same functionality as Hangouts, but the addition of the snooze feature sure is a welcomed addition, as it's useful for both personal and business use. The implementation of this feature is vastly different on Hangouts Chat, though, as it not only offers you a chance to mute notification for a specific time, but it also adds the aforementioned moon icon to your status, and lets your coworkers know when you'll be back, while a regular mute switch is available in Hangouts. It is worth noting that this feature will roll out to Hangouts Chat gradually, so if it is still not available to you, Google asks you to wait a bit, as it will become available to everyone within 15 days.