Beginning November 2021, on Windows (Windows 10 and later) devices running the OneDrive sync app, lists are available for viewing and editing when you're offline, too. This change is pushed out with a Windows update.
With List sync, we synchronize the list data from the cloud to your Windows device, making fast list operations possible and allowing you to continue your work even when you're offline, you lose your internet connection, or you run into a service disruption in the app. The data is stored in a local database under the user’s profile directory and requests are handled through a secure localhost HTTP server. Lists sync runs as a separate background process (Microsoft Nucleus.exe).
List sync doesn't change how you work with the Lists web app. It's still available for you to work on in a browser as before.
By default sync will be enabled on all lists. If you have the ability to work offline you will see a new icon (circle with check mark) next to the list name
List sync is currently supported only on Windows 10 devices. You have to wait for the update to be pushed to you--there is nothing you can install.
A full offline experience for lists—where you can perform all of the operations that are available online—is not yet supported.
Currently, not all types of lists can be synced. The lists that are not supported right now are prevented from syncing, and no “sync icon” appears on the list. Following are the kinds of lists that aren't synced:
Some users may find syncing lists disruptive or cause issues. Users can chose to self-disable sync for themselves by following these instructions: https://support.microsoft.com/en-us/office/edit-lists-offline-41403c3e-1795-4e07-b56b-ae591cbde2f9
Site administrators can disable sync on lists in SharePoint the same way as is done for document libraries. Go to Gear>List Settings>Advanced Settings> and set Offline Client Availability to "No".
Other resources
Complete Microsoft documentation on offline lists