A PowerShell module contains commands (such as cmdlets), functions, variables, and so on.
ShareGate provides a module for supported operations with PowerShell.
Using external PowerShell modules alongside the the ShareGate migration tool module may cause unforeseen behavior. While we do our best to help with these cases, the ShareGate migration tool does not officially support external PowerShell modules.
It is always best to exclusively use the ShareGate migration tool's PowerShell module for your operations.