Not done through natural pollination but through grafting, cannabis-hop hybrid is more tech lab then donkeys and wild horses. Since they are genetically related it isn’t obscene, though the mixing might not develop anything of grander. It might turn out that the hop-cannabis hybrid is useless on both fronts: pretty for gardening and smelling but aesthetically and technologically useless.
Dutch Ganja atricles on growing marjiuana 18.6 Grafting talks about the science, myth and how to of hop-cannabis hybrids:
"The beauty of such a graft is that it would be difficult to identify as marijuana and, possible, the plant would not be covered under marijuana statutes. Unfortunately, the myth is false. It is possible to successfully graft Cannabis with Humulus, but the hops portion will not contain any cannabinoids.
In 1975, the research team of Crombie and Crombie grafted hops scions on Cannabis stocks from both hemp and marijuana (Thailand) plants 205. Cannabis scions were also grafted to hops stocks. In both cases, the Cannabis portion of the graft continued to produce its characteristic amounts of cannabinoids when compared to ungrafted controls, but the hops portions of the grafts contained no cannabinoids. This experiment was well-designed and carried out. Sophisticated methods were used for detecting THC, THCV, CBD, CBC, CBN, and CBG. Yet none of these were detected in the hops portions.