Navigate to Merchant Panel > Start > Tools > Roles, create a copy of existing role and check All privileges for all rows. Merchant with these privileges will have the same privileges as a network owner.
2. Create merchant with owner role
Navigate to Merchant Panel > Start > Tools > Merchants, Click Add merchant button. For merchant role choose the owner role you just created and for the account use the default owner account.
Notice that you need to create this merchant into your main Account (owner's account), only from this account are accessible all transactions, campaigns and banners.
If this merchant will be inserted into any network merchant account he will see data only for this certain account.