I understand the importance of changing pay schedule in QuickBooks Online (QBO), bautista.
Currently, the QuickBooks Online International version doesn't have a payroll functionality inbuilt. This is why, you're not seeing an option to change the pay date in your QBO.
For now, we only offer payroll services to the following countries:
United States
Australia
Canada
United Kingdom
I recommend reaching out to your third-party payroll application for guidance on adjusting the pay period.