The Pages screen will allow you to quickly navigate between Master courses and its Variations, and also manage which pages from a Master are shown in each Variation.
From the Pages screen in the Master course, you can use the dropdown menu in the top left corner to navigate to different Variations -
From a Variation, you can then use the same dropdown menu to quickly navigate back to the Master course -
Please note that account permissions will still apply, and users will only be able to see Variations that are available to them.
You can also manage which pages from the Master display in each variation from the Master course Pages screen.
To do this, click on the setting icons in the top right corner of the relevant page -
...and select Manage in Variations -
You can then quickly select which Variations to show or hide that page in -