Probably a female vitripennis, which is very common at the moment, here (eyes apparently bare and hind femora half black).
No interactions present.
of Syrphus seen in County Durham yesterday - but even so Marmalade Hoverflies were far more numerous!
Lat/Lng: 53.92239259254, -0.84580510854721
OS grid ref: SE758479
Forestry Commission plantation being returned to wooded heathland