That depends on the dilution. Both developers are solvent developers. Higher dilution will reduce the solvent effect, increasing grain and sharpness both.
All things equal D-76 is slightly higher quality (sharpness at a given level of graininess is higher) but you can't really get rid of grain without getting rid of sharpness (unless you minimize enlargement or go with slower films of course).
Perceived acutance may be higher, but resolution appears to increase with solvency I've found from experience. Acutance is something you can give in the dark room, and in scanning.