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Wisconsin
superelevates the high side shoulders (first chart).  Is there an issue
with barrier height when a shoulder breaks away from the superelevation (second
chart)?

Yes, there could be containment issues with barriers placed off a shoulder for the second situation you illustrated (roadway has positive superelevation and shoulder has negative superelevation).  If the difference in slopes is severe enough, the vehicle could become an airborne projectile as it exits the roadway – similar to the effects of vehicles rolling over the front slope breakpoint of a median ditch in the cable project.  To my knowledge, there have not been any studies to evaluate vehicle trajectories or  barrier placement and containment for these situations.  There is an NCHRP project that is investigating barriers placed on curved, superelevated roadways, but I am not sure if they will be investigating situations with differing roadway and shoulder superelevations.