I would say over and underpaid both do exist in scenarios where one party has undue/extortive power over the other. They don't exist in a well-functioning labor market.
On the employers side it could be something like monopsony where the employee can only chose to work at any wage or starve because no other jobs are available.
On the employees side it could be something like a politicians relatives getting high paying job because otherwise the politician will cause problems for the company.
Edit: I don't know if I misread your comment or you edited it, but it I think these coercions are covered by it.
I agree, but none of that is even close to happening here… the market is mostly free and fairly efficient.
If anything, price information is not 100% transparent and that tends to benefit employers, but that exerts downward pressure on the wage rather than the opposite.
