Range and location would be nice. For now I'll assume the location is where Shikamaru VS Temari happened. Both have knowledge on each other so it will be difficult for either Shino or Shikamaru to outsmart the other. Shikamaru is smarter than Shino but Shino is not far behind.
As for offensive attacks go, Shikamaru has shadow stitching and can possess other people's shadows by throwing kunai at them. Shino can use a huge mob of bugs to eat the enemy until they fall unconscious. Shikamaru hasn't shown many ways to kill a huge mob of bugs though so I give the victory to Shino. Although Shikamaru can exploit the shadows that the bugs create and use it to trap Shino, Shino will probably spread the bugs around so that this doesn't happen.