Effect on Large Company on Redistributing Profit from Shareholder to Employees
What other economic impacts would be expected if Disney reduced it's
  net profit margin by 10% purely by increasing low wage employee
  remuneration?


The reduction of net profit margin might exceed the percentage of wage increase if benefits, insurance premiums, and any [Disney's] other obligations are tied to wages.

Likewise, a reduction of net profit margins might prompt shareholders to dump Disney stocks and invest in other companies they consider more profitable and/or unlikelier to act to the detriment of shareholders.

Companies with significant levels of debt might experience an increase in financial costs (higher interest rates) if --for instance-- the reduction of profit margin prompts a rating agency to lower the company's grade a notch.

This answer is neither an exhaustive list of possible impacts nor an assessment of whether or not wages at large corporations currently are at fair levels.