Black flies mating. I think these are Fever flies Dilophus febrilis as they are black and the femal has smokey wings (but I have been wrong before).
No interactions present.
Thanks for looking at this and suggesting an id.
I am having great difficulty with these insects as is obvious from other posts which you have contributed to. But it is better to try to get an id even if there is not much confidence behind it.
I'm struggling with them as well! A good close-up of the front legs and/or a side view of the thorax should be enough to sort out the genus, but to sort out the species it's a mix of wing venation, details of the legs, and colours of various parts of the body and the hairs on the body, so they're not easy to do from photos.
Entomologist and biological recorder
Thanks for the encouragement! Trying to get the details you need probably means that the fly has the choice of whether to be patient whilst you photograph every angle from close range; captured; or its most likely option, fly off before you get too close.
I will keep trying.
Lat/Lng: 52.7, -2.5
OS grid ref: SJ7112