I have LLC sole member. will be jointly filing with my wife. question is, can i do standard deduction for both of us then do itemized deduction for the LLC expenses?

A single member LLC that has not incorporated is considered a disregarded entity for tax purposes.  You will file a Schedule C to report the income and expenses as a sole proprietor.  The Schedule C is included with and part of your personal tax return, Form 1040.  The net income or loss from self employment reported on Schedule C are entered on your personal tax return, Schedule 1 Line 3 and Form 1040 Line 7a

On your personal tax return you can only use either the Standard Deduction or Itemized Deductions, whichever is greater.  Itemized deductions are entered on Schedule A and only personal deductions can be reported on a Schedule A.  

The total of all your itemized deductions on Schedule A must be greater than the standard deduction for your filing status to have any tax benefit.

Standard deductions for 2019

• Single - $12,200 add $1,650 if age 65 or older
• Married Filing Separately - $12,200 add $1,300 if age 65 or older
• Married Filing Jointly - $24,400 add $1,300 for each spouse age 65 or older
• Head of Household - $18,350 add $1,650 if age 65 or older

can i do standard deduction for both of us then do itemized deduction for the LLC expenses?

Regardless of what you do on the personal 1040 side, you have "no choice" but to itemize your business expenses on the SCH C.  Doesn't matter what you do on the SCH A, be it standard deduction or itemized deductions.