Hello,
according to the traffic sign it is a "real" roundabout: https://www.mapillary.com/app/?lat=50.820384&lng=6.3457201&z=17&focus=photo&pKey=1370345144204106.
But in OSM it should be tagged as https://wiki.openstreetmap.org/wiki/Tag:highway%3Dmini_roundabout on  the junction node becuase it is traversable.
Regards