Both Neji and Sakura are individually stronger than Shikamaru and Asuma. Neji's kaiten can protect him from anything in Asuma's arsenal and in close range, I believe Neji will trump Asuma with a moderate amount of difficulty. Neji's 360 degree vision and his ability to see chakra allows him to tell when a jutsu is going to be prepared, then he can easily warn Sakura if Shikamaru manages to hide his shadows from Sakura's line of sight.
Sakura has been trained in the art of evasion by Tsunade so it is a skill deeply ingrained withing Sakura's skill set as shown in Sakura's fight alongside Chiyo against Sasori. This should allow her to dodge Asuma's dust cloud which Ino managed to not only rescue Chouji but save herself from the attack. I doubt burning ash is that lethal and Sakura can survive it with minimal injuries which can be shrugged off. However it is a bad idea for Sakura to get close to either Asuma of Shikamaru because of Asuma's wind blades and Shikamaru's ability to connect his shadows to Sakura's. In this case, Sakura would have to rely on mid ranged attacks such as poisoned kunais, sleep gas bombs and area of effect shockwaves, which could prove to be deadly.
Neji could survive any shock waves Sakura decides to use through full body blow but the same can not be said of Shikamaru or Asuma. Lastly, I believe Neji's vacuum palm will be more effective at mid range than Asuma's ninjutsu since Neji's does not require hand seals and can travel faster than Asuma's.
Neji and Sakura win low-mid difficulty IMO.