You cannot file W-2s for recipient's with ITINs;, you should file Form 1042-S. Form 1042-S is used to report the following:
File Form 1042-S, Foreign Person's U.S. Source Income Subject to Withholding, to report amounts paid to foreign persons (including persons presumed to be foreign) that are subject to withholding, even if no amount is deducted and withheld from the payment because of a treaty or Code exception to taxation or if any amount withheld was repaid to the payee.
DO NOT use Form 1042-S to report items required to be reported on any of the following forms:
Form W-2 (wages and other compensation made to employees (other than compensation for dependent personal services for which the beneficial owner is claiming treaty benefits, including wages in the form of group-term life insurance).
Any Form 1099.