Enschede
Osnabrück has two universities and one shared sports programme. The Zentrum für Hochschulsport (ZfH) is run jointly by Osnabrück University and Osnabrück University of Applied Sciences and offers up to 150 activities a semester; the basic programme is free for students. For volleyball it has courses and supervised play sessions, and in summer two beach courts at the sports centre on Jahnstraße.
Places in those play sessions are handed out one week at a time, though, and people from outside the universities can join a beach game but can't book a court. So if you want to play with people from town, from work or from both universities, you need a game of your own. There isn't one on TheQuickSport in Osnabrück yet.
You can create the first one yourself. With your account, set up a free starter game: choose the sport, place, time and level, and up to 24 players can sign up. It goes live straight away. Send the link to your course's WhatsApp group, your flat or your team. You can create three starter games in total, one at a time.
For a regular hall slot, a club is usually the way in: the Stadtsportbund Osnabrück brings together more than 100 of the city's sports clubs. If your game turns into a regular slot with a fee, apply for the organiser platform: no commission on the game fee, players pay upfront online, and waiting lists, reminders and payouts are handled for you. The nearest running games are in Enschede: the RB 61 runs hourly from Osnabrück Hauptbahnhof straight to Hengelo, and from there a train takes you on to Enschede.