This requires you to be in your normal wallet and 2FA must be disabled.
If you need a secondary Bitbox01 to try this, reach out to support@bitbox.swiss
In order to access the legacy hidden wallet on your Bitbox01:
1. Unlock the Bitbox01 with your normal device password
2. Go to "Manage Device"
3. Open the in app guide (button in upper right corner)
4. Click on "How do I access the legacy hidden wallet?"
5. Click the red "Enable legacy hidden wallet" button
6. Unplug the BitBox01 and re-plug it
7. Enter your hidden wallet device password
You are now in the legacy hidden wallet