Can a person being as non-executive director of a pvt company work as a full time employee to other?

Yes, he an work in MNC as full time employment.

Subject to condition that Articles of Association of such Pvt Ltd company allows such person to work in other companies as an fill time employee.

So if AOA of such Pvt Ltd is silent regarding section 164 & 167 excluding the provisions mentioned in the companies act 2013. He can work.

Make sure that In letter of offer or in polices of MNC is also no objection if you are non executive director.

good clarification and information