yes but the page says it im not even lying the page says it with red letters to advise you that you need to take precautions.
But it says nothing about always having to be online. Copied from that very guide.
Installing CBHC incorrectly can brick your Wii U! Make sure to follow the following rules when installing CBHC:
- The DS game has to be legitimately installed from the eShop!
- Don’t format the system while CBHC is installed!
- Don’t delete the user account that bought the DS Virtual Console game!
- Don’t re-install the same game using WUP Installer or from the eShop!
- Don’t install Haxchi over CBHC! (You will not brick, but it will cause a boot-loop! Hold A when booting to access the Homebrew Launcher and uninstall CBHC.)
- Don’t uninstall the DS Virtual Console game without
properly uninstalling CBHC first!
- Don’t move the DS Virtual Console game to a USB drive!