What would be the outcome or procedures taken if a significant portion of the data of a company is located overseas and outside the jurisdiction or audit universe?

Wouldn't it be a scope limitation resulting in a qualified opinion? What would be alternative procedures compensate? Would alternative methods be sufficient to prevent a limitation of scope?

How will the risk assessment be modified to account for lack of evidence?

Are there specific rules and regulations that have to be considered? I know classified information a clearance would be required to review such information.