Yes, the White Label 2.0+ plugin is compatible with WordPress Multisite network installations.
Each multisite in a network can have its own independent login page design and settings.
It’s recommend that you use White Label Pro for Multisites.
Notes for multisite users
White Label will allow you to choose White Label Administrators. These administrators set rules to limit what plugins, menus and other settings that regular administrators & users cannot.
As a Super Administrator of a WordPress multisite installation you will always bypass all White Label rules.
Super administrators will not show up as White Label Administrators in the settings, so don’t worry. Super admins have full access by default.
You can read more about WordPress Multisites & Super Admins here