As a user having an Administrator profile in Zoho CRM, can I view the expenses/expense reports created by my Sales Executives?

No, Users with Administrator Profile cannot view the expenses/Reports created by their Sales Executives.

Currently, only the Expenses and Expense reports module have been synced with Zoho CRM. These modules can be accessed only by the respective Sales Executives.

On a brighter note, as an Admin user in Zoho Expense, you can view all the expenses created across the organization from All Approvals section and run analytics for the same.