Miniman's answer to this question Is there any way to get expanded critical range or higher critical multipliers? prompted me to theorycraft the following:
Rogue(18)/Barbarian(2)
Reckless Attack (PHB pg. 48) grants advantage on attacks, but it also grants anything attacking you advantage until your next turn.
However, Elusive (PHB pg. 96) states that no attacker can have advantage against you unless you're incapacitated.
The condition for Sneak Attack has been met, and the character Reckless Attacks with a Scimitar, but opts to use Strength. The Finesse weapon requirement has been met, and advantage has been gained, so Sneak Attack applies. Enemies are granted advantage, but simultaneously, they are denied advantage.
The above combination has two specific features that directly counter each other. Now, I personally would rule this as the higher level feature trumps the lower level feature in this specific case. However, I can't find an official rule or ruling that states that one feature trumps the other.