. Technicals aside, China needs more B-52 style multi purpose bombers than a ultra high tech and ultra expensive cold-war style stealth bomber.
That ship has sailed, though. B-52's are modernized and kept around because they are already paid for many times over and the airframe has been flexible enough to handle improvements regarding weapons system and avionics and the US is still willing to put up with its 8 engines, which also is kind of a product of necessity, as the B-52 original rol as a low level bomber is completely gone.
It doesn't really make sense to design a B-52 in this time and age. Its probably cheaper overall to just make your VLO design as flexible and multirole as a B-52, as at least its survivability is more future proof than an airliner sized and shaped bomber.