Unfortunately, how contractors get really screwed is when they run into a real asshole client. Once this happens they are reported to upwork (for not doing free work usually). Good contractors that worked for us were routinely banned.
[I only have been on the client side.]
"As a general rule, wages earned by nonresident aliens for services performed outside of the United States for any employer are foreign source income and therefore are not subject to reporting and withholding of U.S. federal income tax."
The contractor in Russia that is registered on payoneer can issue an invoice to you, with an US bank account number.