You cannot change from standard to itemized deductions on the Virginia return. According to the Virginia Tax:
If you claimed the standard deduction on your federal income tax return, you must also claim the standard deduction on your Virginia return.
If you claim itemized deductions on your federal income tax return, you must also itemize your deductions on your Virginia return. This requirement applies even if using the standard deduction would result in a greater tax benefit on your Virginia return.
Here is the full page about deductions in Virginia:
https://tax.virginia.gov/deductions