You can use multi login functionality to import data into different Linnworks Accounts, the same way as Multi Login for Linnworks system is done. Unlike Linnworks main application data import tool can be run simultaneously for multiple accounts.
To start data import tool with the multi login functionality you need to supply dbselect argument to the data import tool. The easiest way to do this is to create a shortcut on the desktop that points to Multilogin Data Import
C:\Program Files (x86)\Linn Systems\Linnworks\ImportUI.exe dbselect