Dual Boot Windows 10 and macOS to External Drive on Macbook
Firstly go through steps: Install Windows 10 to External Drive on Macbook
The following steps will allow you to have one or more macOS installation in a single APFS volume on the external drive.
Install macOS
- Boot into Windows and resize Windows partition to make space for macOS installations.
- Create new partition in Windows for macOS installations.
- Boot into macOS and open Disk Utility.
- Format newly created partition to APFS.
- Download macOS installation from the macOS App Store.
- Once installer starts go through process and select newly created APFS partition for destination disk.
Install Additional macOS versions
- Additional macOS versions can be installed to the same APFS partition created above.
- You must first create a new APFS volume within the APFS partition for the new macOS installation.