You can't. Using a domain account in this manner means that you are on a trusted system, so far as the domain is concerned. You must use SQL Server based-logins if your systems are not joined to the domain.

There is a workaround, but it's not pretty. What it means is that the account users are using locally must be created locally on the server where SQL Server is running and the passwords must be kept in synch. This sort of "pass-through" authentication works, but it's a bear to maintain. So your best option is to either get those systems on the same domain or to live with the use of SQL Server based logins.